# The licence is not the bill. Ingest is the bill — and it grows with your traffic, not your headcount. *Observability & APM — a TechBag decision guide. Last reviewed 2026-10-03.* > Every product here meters on volume: hosts monitored, gigabytes ingested, events captured, sessions recorded. A per-user mental model — the one that works everywhere else on this site — produces a forecast that is wrong by an order of magnitude. **The checkable fact:** Datadog publishes three different meters inside one platform: APM and Infrastructure per host, Log Management per GB ingested *plus* per million events indexed, RUM per thousand sessions. Model your volumes against the meter, not the rate. - Canonical: https://www.thetechbag.com/browse/devops/observability-apm - Category: [DevOps](https://www.thetechbag.com/browse/devops) - Products compared: 23 ## What observability & apm actually is Observability is the practice of keeping enough telemetry — logs, metrics, traces — that you can answer a question you did not anticipate. Monitoring answers questions you wrote a check for in advance. That distinction sounds academic until you see the bill: keeping the detail is exactly what you pay for. The twenty-three products below split by meter more usefully than by feature. Eight are per-host or per-GB platform modules. Five are event-metered and materially cheaper for the same job at small volumes. Five are quote-only. And two — Mixpanel’s pair — are product analytics rather than infrastructure observability, included because the meter and the buying team overlap, and labelled so you do not buy one for the other. And one — Kentik — watches the network rather than the application, on a published annual tier sized in flows per second. **The most common mis-purchase.** The **pricing meter**. This is the category’s equivalent of a firewall’s throughput figure: a per-host quote and a per-GB quote for the same estate can differ by **an order of magnitude**, and no comparison on the internet models it against your volumes. Ask every vendor to price your *actual* host count, ingest volume and event rate — then compare the totals, never the rates. ## Four terms, resolved These are not tiers. Observability is not monitoring done better — it answers questions you never wrote a check for, from telemetry you pay to keep, at a materially different cost. ### Monitoring vs observability Did you know in advance what to check? ### Observability vs APM The whole estate, or the application request? ### Logs vs metrics vs traces Which one answers your question, and what does it cost to keep? ### APM vs RUM vs error tracking Server-side performance, device experience, or exceptions? None of these is a better product than the others. They answer different questions at different meters, and the expensive mistake is buying platform-grade telemetry for a question that error tracking answers for a few hundred dollars a month. ## The decision variables Seven variables move the shortlist. The first one moves it more than the other six combined. **The pricing meter.** Per host, per GB ingested, per million events indexed, per session, per user — or quote-only. Same estate, different meters, order-of-magnitude difference. **Retention, and what keeping it costs.** The licence covers the first tranche. Shortening retention to control cost is the standard reflex, and the incident then falls outside the window. **Language and runtime coverage.** For the stack you actually run, including the older service nobody wants to touch. **Cardinality limits.** The failure mode nobody forecasts: one well-meant custom tag turns a metric into millions of time series. **Alerting and on-call integration.** Whether alerts reach the rota you already run, or need a second product. **Open-source viability.** Prometheus, Grafana and OpenTelemetry are genuinely credible here. A page pretending otherwise is not worth reading. **India region and residency.** Documented for Dynatrace (AWS Mumbai) and Elastic (Mumbai and Pune regions); Datadog has no India site; the rest do not document one — logs frequently carry personal data, so confirm rather than assume. ## The 23 products Every product carries one stated limitation. Prices are USD with an indicative INR conversion, tier- and term-matched where the vendor publishes one. ### Elastic Observability — Elastic - **Who it's for:** Teams already running the ELK stack for logs — this formalises what they have rather than migrating — and estates large enough that per-host pricing has become the problem. - **The honest limitation:** You run the cluster unless you buy Elastic Cloud, and operating Elasticsearch well at scale is real engineering work. The correlation UX is less polished than Datadog’s and dashboards need more assembly. - **Price:** Free → tier — engine free under AGPL plus a subscription tier; Elastic Cloud Hosted priced on PROVISIONED RESOURCES rather than per host or per GB (reported ~$99/mo Standard to ~$184/mo Enterprise at entry size), or Serverless on consumption - **Details:** https://www.thetechbag.com/elastic/elastic-observability ### Datadog APM — Datadog - **Who it's for:** Estates running microservices that need to follow one request across many services, and that already accept a platform bill rather than a per-tool one. - **The honest limitation:** The meter is per host, so the bill tracks your infrastructure rather than your traffic — and it compounds with every other Datadog module you enable. Cost management is the standing operational task, not a one-time negotiation. Datadog runs no India site: its Asia-Pacific sites are AP1 (Japan) and AP2 (Australia). - **Price:** Per host, published — per host / month, published list; distributed tracing across services with the span-level detail that names the slow hop — billed on top of Infrastructure Monitoring rather than instead of it - **Details:** https://www.thetechbag.com/datadog/datadog-apm ### Datadog Infrastructure Monitoring — Datadog - **Who it's for:** Teams that want one place for infrastructure health across cloud accounts, and are choosing the platform deliberately rather than by accident. - **The honest limitation:** Metrics only: it will tell you the p99 got worse and not which span caused it. Custom metrics and high cardinality are separately metered, and cardinality is the line that multiplies a bill without traffic multiplying. Datadog runs no India site: its Asia-Pacific sites are AP1 (Japan) and AP2 (Australia). - **Price:** Per host, published — per host / month, published list; the base layer of the platform — host, container and cloud-service metrics with the dashboards and alerting most estates start from - **Details:** https://www.thetechbag.com/datadog/datadog-infrastructure-monitoring ### Datadog Log Management — Datadog - **Who it's for:** Estates whose debugging happens in logs and who are prepared to decide, deliberately, which logs are worth indexing. - **The honest limitation:** Two meters on one product is where forecasts break: teams model ingest and forget indexing. Almost every runaway observability bill in this category is a log bill. Datadog runs no India site: its Asia-Pacific sites are AP1 (Japan) and AP2 (Australia). - **Price:** Per GB + per million events — per GB ingested PLUS per million events indexed, published list; ingest and indexing are separate meters, so what you keep searchable costs more than what you merely collect - **Details:** https://www.thetechbag.com/datadog/datadog-log-management ### Datadog Digital Experience Monitoring — Datadog - **Who it's for:** Teams whose users report slowness that server-side metrics insist is not happening — the gap between what the server did and what the device experienced. - **The honest limitation:** Session-metered, so a traffic spike is a bill spike with no infrastructure change to explain it. Synthetics are a third meter again. Datadog runs no India site: its Asia-Pacific sites are AP1 (Japan) and AP2 (Australia). - **Price:** Per session, published — per 1,000 sessions / month for RUM, with synthetic tests metered separately by run; what the browser or mobile app actually experienced, including the network and third-party scripts the backend never sees - **Details:** https://www.thetechbag.com/datadog/datadog-digital-experience ### Sentry Error Monitoring — Sentry - **Who it's for:** Teams whose actual question is “why did that crash, in which release, for how many people” — answered at a fraction of full APM pricing. - **The honest limitation:** Errors and performance for the application, not the infrastructure: no host metrics, no cloud-service integration, no log platform. It is deliberately one job done well rather than a platform. - **Price:** From ~$26/mo (≈ ₹2,158) — per month on the Team tier (about ₹2,158), Business about $80, both annual; metered on events captured rather than hosts run — exceptions grouped by fingerprint with the release, the commit and the users affected - **Details:** https://www.thetechbag.com/sentry/sentry-error-monitoring ### Sentry Performance Monitoring — Sentry - **Who it's for:** Engineering teams that want tracing tied to the commit that caused the regression, without adopting a per-host platform. - **The honest limitation:** Sampled by design and scoped to the application — it will not replace infrastructure monitoring, and deep cloud-service telemetry is outside it. - **Price:** In the Sentry tiers — metered on transactions/spans within the same published Sentry tiers; developer-first tracing joined to the errors and the release that introduced them - **Details:** https://www.thetechbag.com/sentry/sentry-performance-monitoring ### Sentry Session Replay — Sentry - **Who it's for:** Teams losing time to bugs that cannot be reproduced from a stack trace alone. - **The honest limitation:** Replays are a separate meter and privacy masking must be configured deliberately — an unmasked replay of a checkout page is a data-protection problem, not a debugging win. - **Price:** Per replay, in the tiers — metered per replay within the Sentry tiers; a recording of the session that produced the error, so the reproduction step is watching rather than guessing - **Details:** https://www.thetechbag.com/sentry/sentry-session-replay ### Splunk Observability Cloud — Splunk - **Who it's for:** Estates that want every trace kept rather than sampled, and that are already in the Cisco/Splunk relationship — a distinct SKU from Splunk Enterprise Security, which is carded on the Security category. - **The honest limitation:** The published figures are starting prices per host, so the bill tracks infrastructure like Datadog's, and the final number is still a quote. Full-fidelity tracing is a genuine differentiator and a genuine volume commitment. Splunk documents no India realm for Observability Cloud. - **Price:** $15–75 / host (≈ ₹1,245) — per host / month billed annually, published starting prices: Infrastructure $15, App & Infra $60, End-to-End $75 (adds RUM and browser synthetics); a full-fidelity platform built on OpenTelemetry with no-sample tracing - **Details:** https://www.thetechbag.com/splunk/splunk-observability-cloud ### Splunk ITSI — Splunk - **Who it's for:** Large estates already ingesting into Splunk whose problem is alert volume rather than missing telemetry. - **The honest limitation:** It assumes the Splunk platform underneath and its value is proportional to how much you already ingest there. Service modelling is configuration work measured in weeks, not a switch. - **Price:** Quote — not published — quoted on the Splunk platform; service-level health modelling and AIOps event correlation over data the platform already holds — the layer that turns thousands of alerts into a handful of service states - **Details:** https://www.thetechbag.com/splunk/splunk-itsi ### Quest Foglight Cloud — Quest - **Who it's for:** Estates already running Foglight for databases that want the same console over cloud infrastructure rather than a second platform. - **The honest limitation:** Narrower application-tracing depth than the observability specialists; its strength is the database line, and buying it as a general APM is buying the wrong half of the portfolio. - **Price:** Quote — quoted per monitored resource; SaaS-delivered infrastructure and application monitoring from the vendor whose depth is databases — the cloud front end to a Foglight estate - **Details:** https://www.thetechbag.com/quest/quest-foglight-cloud ### Quest Foglight Evolve — Quest - **Who it's for:** Estates with a large virtualised footprint that need capacity forecasting alongside health, particularly through a hypervisor migration. - **The honest limitation:** Infrastructure-scoped: no application tracing and no log platform. Its natural buyer is the virtualisation team, not the engineering team this page is written for. - **Price:** Quote — quoted per monitored host or VM; virtual and cloud infrastructure monitoring with capacity planning — built for VMware-shaped estates and their migrations - **Details:** https://www.thetechbag.com/quest/quest-foglight-evolve ### Mixpanel Product Analytics — Mixpanel - **Who it's for:** Product and engineering teams asking which features are used and where people drop out — a different question from whether the system is up. - **The honest limitation:** This is product analytics, not infrastructure observability: it will not tell you a service is down or a query is slow. Included here because the event meter and the buying team overlap, not because it substitutes for APM. - **Price:** ~$0.28 / 1k events — about $0.28 per 1,000 events over the free allowance, Enterprise from roughly $25–30k a year; product analytics — what users did in the product, funnels and retention, not whether the server was healthy - **Details:** https://www.thetechbag.com/mixpanel/mixpanel-product-analytics ### Mixpanel Session Replay — Mixpanel - **Who it's for:** Teams that have the funnel data and still cannot explain the drop-off at one step. - **The honest limitation:** Tied to the Mixpanel platform and to product questions rather than engineering ones. Privacy masking is a deliberate configuration, not a default. - **Price:** In the event tiers — metered within the Mixpanel event tiers; replays joined to the analytics events, so a funnel drop-off can be watched rather than inferred - **Details:** https://www.thetechbag.com/mixpanel/mixpanel-session-replay ### Dynatrace Application & Infrastructure Observability — Dynatrace - **Who it's for:** Estates where incident time is lost finding the cause rather than fixing it, and that want one agent instead of per-service instrumentation. - **The honest limitation:** Full-stack is priced per 8 GiB of host memory, so large-memory hosts count several times over. Root cause is only as good as the coverage — hops the agent does not see are gaps in the map. The Mumbai region is documented; a written storage commitment is a contract question. - **Price:** $29–58 / host (≈ ₹2,407) — per host / month published: $29 for infrastructure monitoring, $58 per 8 GiB of host memory for full-stack — drawn down from one annual Dynatrace Platform Subscription; one agent instruments hosts, processes and code, and a live dependency map is what the root-cause analysis reasons over - **Details:** https://www.thetechbag.com/dynatrace/dynatrace-observability ### Dynatrace Log Analytics — Dynatrace - **Who it's for:** Teams that want logs in the same store as their traces, and that will set retention per source rather than keep everything for a year. - **The honest limitation:** Pay-per-query charges per GiB scanned, so wide queries over long windows add up — choose between pay-per-query and bundled on how the team actually searches. DQL is new to most teams. - **Price:** $0.20 / GiB ingest — per GiB published, split three ways: $0.20 to ingest, $0.0007 per GiB-day to retain and $0.0035 per GiB scanned by queries — or $0.02 per GiB-day with queries bundled; logs sit in Grail beside the traces and metrics they explain - **Details:** https://www.thetechbag.com/dynatrace/dynatrace-log-analytics ### Dynatrace Digital Experience Monitoring — Dynatrace - **Who it's for:** Digital and product teams that need a slow page to arrive with the backend service that caused it, and replay evidence behind a conversion drop. - **The honest limitation:** Cost scales with sessions, so a high-traffic consumer app needs a sampling policy decided up front, and replay is safe only once masking is configured and reviewed. - **Price:** $2.25 / 1,000 sessions — per 1,000 real-user sessions published ($4.50 with Session Replay), synthetic browser tests at $4.50 per 1,000 actions; each session is joined to the backend trace behind it. A Leader in the 2025 Gartner Magic Quadrant for Digital Experience Monitoring - **Details:** https://www.thetechbag.com/dynatrace/dynatrace-digital-experience ### SolarWinds Observability SaaS — SolarWinds - **Who it's for:** Teams that want network, infrastructure, APM and logs in one SaaS with every module on a published price, and a bridge to self-hosted SolarWinds. - **The honest limitation:** Data sits in North America, Frankfurt or Australia — no India region; each module is priced separately, so model the whole bill; a Niche Player in Gartner’s Observability Platforms Magic Quadrant. - **Price:** $15.75 / node (≈ ₹1,307) — per node a month for network and infrastructure; APM $27.50 per service, logs $5 per GB, databases $70 per instance, synthetics and RUM priced apart — multi-year contracts billed annually - **Details:** https://www.thetechbag.com/solarwinds/solarwinds-observability-saas ### SolarWinds Observability Self-Hosted — SolarWinds - **Who it's for:** Network and infrastructure teams that must keep monitoring data on their own servers — including in India — with the Orion-era modules in one platform. - **The honest limitation:** You run and patch it (critical flaws fixed in September 2026), and when the subscription lapses polling of new data stops; SUNBURST (2020) came through this platform’s build system — the SEC case was dismissed in November 2025. - **Price:** $8 / node (≈ ₹664) — per node a month on multi-year contracts billed annually (Essentials; Advanced $14, Premier $17.50); Enterprise from 500 nodes; NPM, SAM and other modules still sold singly on quote - **Details:** https://www.thetechbag.com/solarwinds/solarwinds-observability-self-hosted ### OpenText AI Operations Management (formerly Operations Bridge) — OpenText - **Who it's for:** Operations teams running many monitoring tools who want one event view above them — 1,000+ prebuilt integrations, AI correlation OpenText says cuts event volume by 30–95%, and runbooks gated by approvals. - **The honest limitation:** An event and AIOps layer, not deep APM: code-level traces and logs come from the Application Observability add-on or the tools it ingests. CVE-2025-3476 (CVSS 9.4) hit the event console in 2023.05 to 24.4; no OpenText-hosted India region is published. - **Price:** Quote — quote-only in two editions — Express for private cloud, Premium for private or public cloud with real user monitoring — plus paid add-ons for integrations, event and metric analytics, GenAI incident management, observability, automation and discovery/CMDB; SaaS, hybrid, on-premises or air-gapped - **Details:** https://www.thetechbag.com/opentext/opentext-ai-operations-management ### Kentik (an Infoblox company) — Infoblox - **Who it's for:** Network and platform teams that need to see traffic across data centres, clouds and the internet — flow, routing and synthetic tests — rather than application traces. - **The honest limitation:** Network observability, not APM: it does not trace code. Data is stored in Ashburn, Virginia or Frankfurt, with no India region, full-resolution flow is kept 45 days by default, and the published price is a US list for annual contracts only. - **Price:** $2,000 / mo (≈ ₹1,66,000) — Pro from US$2,000 a month billed annually (US$24,000 a year) with 50 users, 1,000 flows per second and 25 monitored devices included, a 30-day trial and Premier by quote; network flow, device metrics, synthetic tests and cloud flow logs; Infoblox acquired Kentik in August 2026 - **Details:** https://www.thetechbag.com/infoblox/infoblox-kentik ### IBM Instana Observability — IBM - **Who it's for:** Teams that want one-second, automatically discovered traces and dependency maps without hand instrumentation, priced per host rather than per GB. - **The honest limitation:** MVS metering follows infrastructure size, not traffic, and IBM should confirm in writing how containers and Kubernetes nodes are counted; retention is not published. - **Price:** $21.20 (≈ ₹1,760) — per managed virtual server (MVS, roughly a host) / month on SaaS; $0.03 per MVS-hour pay-per-use; self-hosted $385.20 per MVS / year; 14-day trial; SaaS in Mumbai since April 2024 (IBM staff blog) - **Details:** https://www.thetechbag.com/ibm/ibm-instana ### Observe by Snowflake — Snowflake - **Who it's for:** Teams whose Datadog or Splunk bill grew faster than their traffic and who want logs, metrics and traces in an open lakehouse with an AI SRE on top. - **The honest limitation:** A committed-ingest subscription, so you size the commitment up front; no Indian hosting region is documented, and RUM and session replay are not listed. Snowflake bought Observe in 2026, so packaging is still settling. - **Price:** $0.49 / GiB (≈ ₹41) — logs from $0.49 per GiB ingested, traces from $0.59 per GiB, metrics from $0.008 per data point per minute; compute, unlimited users and 30-day retention for logs and traces included (metrics 13 months); committed-volume subscription - **Details:** https://www.thetechbag.com/snowflake/snowflake-observe ## Why each constraint rules out what it does The full narrowing logic, as prose. Nothing here is hidden behind an interaction. **published pricing.** Rules out Elastic Observability, Splunk ITSI, Quest Foglight Cloud, Quest Foglight Evolve and OpenText AI Operations Management (formerly Operations Bridge) — quote-only: no published list, so the quote is the only real number. That leaves Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Datadog Digital Experience Monitoring, Sentry Error Monitoring, Sentry Performance Monitoring, Sentry Session Replay, Splunk Observability Cloud, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, Dynatrace Digital Experience Monitoring, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted, Kentik (an Infoblox company), IBM Instana Observability and Observe by Snowflake. **not per host.** Rules out Datadog APM, Datadog Infrastructure Monitoring, Splunk Observability Cloud, Dynatrace Application & Infrastructure Observability, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted and IBM Instana Observability — per host, so the bill tracks infrastructure and autoscaling moves it. That leaves Elastic Observability, Datadog Log Management, Datadog Digital Experience Monitoring, Sentry Error Monitoring, Sentry Performance Monitoring, Sentry Session Replay, Splunk ITSI, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Log Analytics, Dynatrace Digital Experience Monitoring, OpenText AI Operations Management (formerly Operations Bridge), Kentik (an Infoblox company) and Observe by Snowflake. **event metering.** Rules out Elastic Observability, Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Splunk Observability Cloud, Splunk ITSI, Quest Foglight Cloud, Quest Foglight Evolve, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted, OpenText AI Operations Management (formerly Operations Bridge), IBM Instana Observability and Observe by Snowflake — not event-metered. That leaves Datadog Digital Experience Monitoring, Sentry Error Monitoring, Sentry Performance Monitoring, Sentry Session Replay, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Digital Experience Monitoring and Kentik (an Infoblox company). **distributed traces.** Rules out Datadog Infrastructure Monitoring, Datadog Log Management, Datadog Digital Experience Monitoring, Sentry Error Monitoring, Sentry Session Replay, Splunk ITSI, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Log Analytics, Dynatrace Digital Experience Monitoring, SolarWinds Observability Self-Hosted, OpenText AI Operations Management (formerly Operations Bridge) and Kentik (an Infoblox company) — no distributed tracing. That leaves Elastic Observability, Datadog APM, Sentry Performance Monitoring, Splunk Observability Cloud, Dynatrace Application & Infrastructure Observability, SolarWinds Observability SaaS, IBM Instana Observability and Observe by Snowflake. **log search.** Rules out Datadog APM, Datadog Infrastructure Monitoring, Datadog Digital Experience Monitoring, Sentry Error Monitoring, Sentry Performance Monitoring, Sentry Session Replay, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Digital Experience Monitoring and OpenText AI Operations Management (formerly Operations Bridge) — not a log platform. That leaves Elastic Observability, Datadog Log Management, Splunk Observability Cloud, Splunk ITSI, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted, Kentik (an Infoblox company), IBM Instana Observability and Observe by Snowflake. **real user monitoring.** Rules out Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Sentry Error Monitoring, Sentry Performance Monitoring, Splunk ITSI, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, SolarWinds Observability Self-Hosted, Kentik (an Infoblox company) and Observe by Snowflake — server-side only: it cannot see what the device experienced. That leaves Elastic Observability, Datadog Digital Experience Monitoring, Sentry Session Replay, Splunk Observability Cloud, Mixpanel Session Replay, Dynatrace Digital Experience Monitoring, SolarWinds Observability SaaS, OpenText AI Operations Management (formerly Operations Bridge) and IBM Instana Observability. **error tracking.** Rules out Elastic Observability, Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Datadog Digital Experience Monitoring, Sentry Performance Monitoring, Sentry Session Replay, Splunk Observability Cloud, Splunk ITSI, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, Dynatrace Digital Experience Monitoring, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted, OpenText AI Operations Management (formerly Operations Bridge), Kentik (an Infoblox company), IBM Instana Observability and Observe by Snowflake — no dedicated error grouping with release and commit context. That leaves Sentry Error Monitoring. **OpenTelemetry-native.** Rules out Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Datadog Digital Experience Monitoring, Sentry Error Monitoring, Sentry Performance Monitoring, Splunk ITSI, Dynatrace Digital Experience Monitoring, OpenText AI Operations Management (formerly Operations Bridge) and IBM Instana Observability — OpenTelemetry is supported but the vendor agent is the primary path; Sentry Session Replay, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Mixpanel Session Replay, SolarWinds Observability Self-Hosted and Kentik (an Infoblox company) — OpenTelemetry support is not documented. That leaves Elastic Observability, Splunk Observability Cloud, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, SolarWinds Observability SaaS and Observe by Snowflake. **one platform.** Rules out Sentry Error Monitoring, Sentry Performance Monitoring, Sentry Session Replay, Quest Foglight Cloud, Quest Foglight Evolve, Mixpanel Product Analytics, Mixpanel Session Replay and Kentik (an Infoblox company) — focused on one job rather than covering the estate. That leaves Elastic Observability, Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Datadog Digital Experience Monitoring, Splunk Observability Cloud, Splunk ITSI, Dynatrace Application & Infrastructure Observability, Dynatrace Log Analytics, Dynatrace Digital Experience Monitoring, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted, OpenText AI Operations Management (formerly Operations Bridge), IBM Instana Observability and Observe by Snowflake. **on-premises.** Rules out Elastic Observability, Datadog APM, Datadog Infrastructure Monitoring, Datadog Log Management, Datadog Digital Experience Monitoring, Sentry Session Replay, Splunk Observability Cloud, Quest Foglight Cloud, Mixpanel Product Analytics, Mixpanel Session Replay, Dynatrace Log Analytics, Dynatrace Digital Experience Monitoring, SolarWinds Observability SaaS, SolarWinds Observability Self-Hosted, Kentik (an Infoblox company), IBM Instana Observability and Observe by Snowflake — SaaS only. That leaves Sentry Error Monitoring, Sentry Performance Monitoring, Splunk ITSI, Quest Foglight Evolve, Dynatrace Application & Infrastructure Observability and OpenText AI Operations Management (formerly Operations Bridge). **India region.** Rules nothing out on published terms. It flags Datadog APM — An India data region for telemetry is not documented on the vendor's pages, Datadog Infrastructure Monitoring — An India data region for telemetry is not documented on the vendor's pages, Datadog Log Management — An India data region for telemetry is not documented on the vendor's pages, Datadog Digital Experience Monitoring — An India data region for telemetry is not documented on the vendor's pages, Sentry Error Monitoring — An India data region for telemetry is not documented on the vendor's pages, Sentry Performance Monitoring — An India data region for telemetry is not documented on the vendor's pages, Sentry Session Replay — An India data region for telemetry is not documented on the vendor's pages, Splunk Observability Cloud — An India data region for telemetry is not documented on the vendor's pages, Splunk ITSI — An India data region for telemetry is not documented on the vendor's pages, Quest Foglight Cloud — An India data region for telemetry is not documented on the vendor's pages, Quest Foglight Evolve — An India data region for telemetry is not documented on the vendor's pages, Mixpanel Product Analytics — An India data region for telemetry is not documented on the vendor's pages, Mixpanel Session Replay — An India data region for telemetry is not documented on the vendor's pages, SolarWinds Observability SaaS — An India data region for telemetry is not documented on the vendor's pages, SolarWinds Observability Self-Hosted — An India data region for telemetry is not documented on the vendor's pages, OpenText AI Operations Management (formerly Operations Bridge) — An India data region for telemetry is not documented on the vendor's pages, Kentik (an Infoblox company) — An India data region for telemetry is not documented on the vendor's pages and Observe by Snowflake — An India data region for telemetry is not documented on the vendor's pages — marked, not removed. **The meter decides the bill, not the rate.** A per-host quote and a per-GB quote for the same estate can differ by an order of magnitude. Datadog alone runs three meters — per host for APM and infrastructure, per GB ingested plus per million events indexed for logs, per session for RUM. Model your own volumes against each meter before comparing any two vendors. **Splunk Observability now publishes per-host starting prices.** Splunk lists Observability Cloud from $15 per host a month (Infrastructure), $60 (App & Infra) and $75 (End-to-End), billed annually. They are starting points, so the quote is still the final number, and ITSI remains quote-only. **Cardinality is the line nobody forecasts.** Add a user ID or request ID as a metric tag and one metric becomes millions of time series. It is the most common cause of a bill that multiplies while traffic does not, and no vendor stops you doing it. **Open source is genuinely viable here.** Prometheus for metrics, Grafana for dashboards, OpenTelemetry for instrumentation, Loki or Elastic for logs. Unlike most categories on this site, the open-source path is credible for real production estates. It costs engineering time instead of licence — typically an owner, not a side project — and that trade is worth making explicitly rather than by default. ## Eight situations, and what each one buys If one of these is your sentence, the shortlist is short. ### We just need to know why it crashed, and in which release **Shortlist:** Sentry Error Monitoring, Sentry Session Replay **Why:** Exceptions grouped by fingerprint with the release, the commit and the affected users — event-metered, published from about $26 a month. **Trade-off:** No infrastructure monitoring and no log platform. If you also need host health, this is half the answer. ### A request crosses six services and nobody owns the latency **Shortlist:** Datadog APM, Splunk Observability Cloud, Sentry Performance Monitoring **Why:** Distributed tracing is the only signal that attributes time per hop across service boundaries. **Trade-off:** Datadog meters per host and compounds with its other modules; Splunk keeps every trace and is also per host, from $60 for App & Infra. ### The bill doubled and traffic only grew 30% **Shortlist:** Sentry Error Monitoring, Mixpanel Product Analytics **Why:** Move from a host or ingest meter to an event meter, and cut what you index rather than what you collect. **Trade-off:** Event-metered tools are narrower. The real fix is usually cardinality and log indexing discipline, not a new vendor. ### Users say it is slow and our server metrics say it is not **Shortlist:** Datadog Digital Experience, Sentry Session Replay, Mixpanel Session Replay **Why:** Only real user monitoring sees the device, the network and the third-party scripts the backend never touches. **Trade-off:** Session-metered, so a traffic spike is a bill spike with no infrastructure change to explain it. ### We will not be locked into a vendor agent **Shortlist:** Splunk Observability Cloud **Why:** OpenTelemetry-native ingest keeps the instrumentation portable, so changing vendor does not mean reinstrumenting. **Trade-off:** Per host from $15 a month, billed annually, and full-fidelity tracing is a real volume commitment. ### Telemetry cannot leave our infrastructure **Shortlist:** Sentry Error Monitoring, Splunk ITSI, Quest Foglight Evolve **Why:** All three offer a self-hosted path where residency or policy forbids SaaS telemetry. **Trade-off:** You own the upgrades, the storage and the scaling — the operational burden the SaaS price was covering. ### We have thousands of alerts and no idea which service is unhealthy **Shortlist:** Splunk ITSI **Why:** Service-level health modelling collapses alert volume into a handful of service states. **Trade-off:** Assumes the Splunk platform underneath, and the service modelling is weeks of configuration. ### We have engineering time and a tight licence budget **Shortlist:** Prometheus + Grafana + OpenTelemetry (open source) **Why:** Genuinely credible for real production estates in this category, unlike most others on this site. Named here because pretending otherwise would waste your time. **Trade-off:** It costs an owner rather than a licence. Budget the person, the storage and the upgrade path — and revisit when that person leaves. ## At scale Scale here means telemetry volume, not team size — which is the whole point of the category. ### 1 telemetry volume — One application, modest traffic - Event-metered tools are far cheaper - Error tracking usually answers the real question - Open source is overkill for one service **The test:** Price the event meter before looking at any platform. ### 2 telemetry volume — Several services, real traffic - Tracing starts earning its price - Log indexing discipline begins to matter - Cardinality becomes a live risk **The test:** Decide what gets indexed versus merely collected. ### 3 telemetry volume — Microservices at scale - Platform consolidation starts to pay - Sampling strategy is now a design decision - Retention windows become a cost lever **The test:** Model the bill at 2× and 10× before signing multi-year. ### 4 telemetry volume — Very high volume - Open source plus a specialist becomes competitive - Vendor commitment discounts require volume forecasts - Cardinality governance needs an owner **The test:** Name the person who owns cardinality. Nobody does until the bill arrives. Where a vendor does not publish list pricing, this page says so rather than repeating a third-party figure. ## Getting out Instrumentation is the lock-in, not the data. **Instrumentation** — Vendor agents mean reinstrumenting; OpenTelemetry means changing an endpoint *(Depends entirely on OTel)* **Dashboards** — Rebuilt in the new tool every time — no interchange format exists *(Not portable)* **Historical telemetry** — Exportable in principle, rarely worth the cost of moving *(Practically lost)* **Alert rules and on-call routing** — Re-authored, and the tuning that made them quiet is re-learned *(Rebuilt)* The practical consequence: instrument with OpenTelemetry from the start if you expect to change vendor, even if you use a vendor agent today. It is the single cheapest insurance in this category. ## What it costs By meter, in USD and INR, modelled at more than one volume. ### Do you already own one? Four checks, in the order most likely to return a yes. - **Your cloud provider — CloudWatch and Azure Monitor are already collecting.** Enough for infrastructure health and basic alerting; they **stop** at cross-service tracing and correlated debugging. - **Your SIEM — It already ingests many of the same logs.** Different question, different meter, and usually longer retention. Read the [SIEM guide](https://www.thetechbag.com/browse/security/siem-log-management) before buying a second log platform. - **Open source — Prometheus, Grafana and OpenTelemetry are genuinely credible here.** Not a licence cost but an engineering one — budget an owner, not a side project. - **Your APM's free tier — Sentry and Datadog both have real free tiers.** Enough to prove the meter against your own volumes before committing. This is the one category on the site where the open-source answer is genuinely competitive for production estates. Saying otherwise would cost you credibility with the engineer reading this. ### What the rest actually cost Three meters, and the published rates that exist. ### What isn't in the licence price - **Ingest and retention overage.** The largest hidden line. The licence covers a tranche; growth and retention are billed on top. - **Custom metrics and cardinality.** Frequently metered separately. One tag can multiply a metric into millions of series. - **Engineering time for open source.** Not a licence, but real and recurring. Budget an owner, storage and an upgrade path. - **Reinstrumentation on vendor change.** Unless you instrumented with OpenTelemetry, changing vendor means changing every service. ## What goes wrong Five ways this purchase goes wrong. Every one of them is a cost surprise rather than a capability gap. - **The second-year bill after traffic grew.** The forecast was built on today's volume against a meter that tracks usage. Model at 2× and 10× before signing a multi-year contract. - **A cardinality explosion from one well-meant tag.** Someone adds a user ID to a metric label. One metric becomes millions of time series and the bill multiplies with no traffic change. - **Retention shortened to control cost.** The reflex works until the incident that matters falls outside the window, and the post-mortem has no data. - **Instrumenting everything, alerting on nothing actionable.** Full telemetry and an on-call rota that ignores the pages. The tool is not the problem; nobody owns alert quality. - **Buying APM when the requirement was error tracking.** Ten times the price for a question that error tracking answers better. Read the boundary section above before shortlisting. ## Questions this guide answers ### What is the difference between monitoring and observability? Monitoring checks things you knew to check — you defined the dashboard and threshold in advance. Observability answers questions you did not anticipate, such as why one specific customer is slow on one build in one region, by keeping high-cardinality telemetry you can slice after the fact. Observability is not monitoring done better; it is a different cost structure, because keeping that detail is exactly what you pay for. ### How is observability priced? On volume, not headcount — which is what makes this category different from everything else on this site. Datadog publishes per host for APM and Infrastructure, per GB ingested plus per million events indexed for logs, and per thousand sessions for RUM. Sentry and Mixpanel meter events. Splunk does not publish list pricing for Observability Cloud. The meter matters far more than the rate: the same estate can differ by an order of magnitude depending on which meter you are quoted. ### Is Prometheus and Grafana a real alternative? Yes, and this is one of the few categories on this site where that is honestly true for production estates. Prometheus for metrics, Grafana for dashboards, OpenTelemetry for instrumentation, Loki or Elastic for logs. It substitutes engineering time for licence cost — you need a named owner rather than a side project, plus storage and an upgrade path. That trade is worth making deliberately; many estates make it by accident and then discover the owner has left. ### Why did our observability bill double when traffic only grew 30%? Almost always one of three things. Cardinality: a new tag such as a user or request ID turned one metric into millions of time series. Log indexing: ingest and indexing are separate meters at Datadog, and indexing everything is expensive. Or a host-count change: moving from a few large instances to many small autoscaled ones multiplies a per-host bill with no traffic change at all. ### Do I need APM if I already have error tracking? Only if the question is where time goes rather than what failed. Error tracking captures the exception, the release and the affected users at a fraction of APM pricing. APM traces a request across services and attributes latency per hop. If a single request crossing six services has no clear owner, you need tracing. If the real question is 'why did that crash', APM is typically a ten-times overpay. --- *Vendor-neutral. Nothing gated. Figures marked [TechBag to confirm] are team-owned and deliberately not guessed.* *TechBag — India-based software reseller and advisory. https://www.thetechbag.com/browse/devops/observability-apm*