LSM-based aggregation (elastic#11117)

Replace existing aggregation implementation with apm-aggregation, the LSM-based aggregator.

changelogs/head.asciidoc

@@ -21,3 +21,9 @@ https://github.com/elastic/apm-server/compare/8.9\...main[View commits]
 - Add a self-instrumentation transaction to the agent config periodic refresh action. {pull}11129[11129]
 - Stop dropping metadata fields from span documents. {pull}11089[11089]
 - Add permissions to reroute events in the integration package. {pull}11168[11168]
+
+[float]
+==== Aggregation improvements
+- Replace aggregation with LSM-based aggregator which has a lower memory footprint {pull}11117[11117]
+- Add `service.language.name` to service destination metrics {pull}11117[11117]
+- Modify per-service transaction groups limit to consider more than service.name; Add per-service service destination groups limit and per-service service transaction groups limit {pull}11117[11117]

dev_docs/trace_metrics.md

@@ -15,26 +15,19 @@ As transactions are observed by APM Server, it groups them according to various
 attributes such as `service.name`, `transaction.name`, and `kubernetes.pod.name`.
 The latency is then recorded in an [HDRHistogram](http://hdrhistogram.org/) for
 that group. Transaction group latency histograms are periodically indexed (every
-minute by default), with configurable precision (defaults to 2 significant figures).
+minute by default), with a fixed precision of 2 significant figures.
 
 To protect against memory exhaustion due to high-cardinality transaction names
 (or other attributes), at any given time, APM Server places a limit on the number
 of services tracked, the number of transaction groups tracked, as well as number
-of groups tracked per service.
-
-By default, the limits are 1,000 services per GB of memory, 5,000 transaction groups
-per GB of memory. When transaction group latency histograms are indexed, the groups
-are reset, enabling a different set of groups to be recorded.
-The per-service limit is 10% of the global limit. For example, for a 2GB APM Server,
-the limits are 2,000 services, 10,000 transaction groups, and for each service,
-there can be a maximum of 1,000 unique transaction groups.
+of groups tracked per service. See [docs](https://www.elastic.co/guide/en/apm/guide/current/data-model-metrics.html#_aggregated_metrics_limits_and_overflows) for limits.
 
 ## Service transaction metrics
 
 Service transaction metrics are similar to Transaction metrics, but with fewer
 dimensions. For example, `transaction.name` is no longer considered during aggregation.
 
-A limit of 1,000 unique service transaction groups per GB of memory is enforced.
+See [docs](https://www.elastic.co/guide/en/apm/guide/current/data-model-metrics.html#_aggregated_metrics_limits_and_overflows) for limits.
 
 ## Service destination metrics
 
@@ -43,15 +36,16 @@ from one service to another. This works much the same as transaction metrics
 aggregation: span events describing an operation that involves another service
 are grouped by the originating and target services, and the span latency is
 accumulated. For these metrics we record only a count and sum, enabling calculation
-of throughput and average latency. A default limit of 10,000 groups is
-imposed.
+of throughput and average latency.
+
+See [docs](https://www.elastic.co/guide/en/apm/guide/current/data-model-metrics.html#_aggregated_metrics_limits_and_overflows) for limits.
 
 ## Service summary metrics
 
 Service summary metrics consider transaction, error, log, and metric events and
 basically produce a summary of all services sending events.
 
-A limit of 1,000 unique service summary groups per GB of memory is enforced.
+See [docs](https://www.elastic.co/guide/en/apm/guide/current/data-model-metrics.html#_aggregated_metrics_limits_and_overflows) for limits.
 
 ## Dealing with sampling
 

docs/data-model.asciidoc

@@ -461,6 +461,7 @@ You can filter and group by these dimensions:
 * `metricset.interval`: A string with the aggregation interval the metricset represents.
 * `numeric_labels`: Key-value object containing numeric labels set globally by the APM agents.
 * `service.environment`: The environment of the service that made the request
+* `service.language.name`: The language name of the service that served the transaction, for example `Go`
 * `service.name`: The name of the service that made the request
 * `service.target.name`: The target service name, for example `customer_db`
 * `service.target.type`: The target service type, for example `mysql`
@@ -540,12 +541,19 @@ there are limits on the number of unique groups tracked at any given time.
 
 Note that all the below limits may change in the future with further improvements.
 
-* For transaction metrics, the limits are 1000 services per GB of APM Server, and 5000 transaction
-groups per GB of APM Server. Additionally, each service may only consume up to 10% of the transaction groups,
+* For all the following metrics, they share a limit of 1000 services per GB of APM Server.
+** For transaction metrics, there is an additional limit of 5000 total transaction groups per GB of APM Server,
+and each service may only consume up to 10% of the transaction groups,
 which is 500 transaction groups per service per GB of APM Server.
-* For service-transaction metrics, the limit is 1000 service transaction groups per GB of APM Server.
-* For service-destination metrics, the limit is a constant of 10000 service destination groups.
-* For service-summary metrics, the limit is 1000 service summary groups per GB of APM Server.
+** For service-transaction metrics, there is an additional limit of 1000 total service transaction groups per GB of APM Server,
+and each service may only consume up to 10% of the service transaction groups,
+which is 100 service transaction groups per service per GB of APM Server.
+** For service-destination metrics, there is an additional limit of a constant 10000 total service destination groups,
+and each service may only consume up to 10% of the service destination groups,
+which is 1000 service destination groups per service.
+** For service-summary metrics, there is no additional limit.
+
+In the above, a service is defined as a combination of `service.name`, `service.environment`, `service.language.name` and `agent.name`.
 
 [float]
 ===== Overflows

docs/data/elasticsearch/service_destination_metric.json

@@ -32,6 +32,9 @@
   },
   "service": {
     "environment": "production",
+    "language": {
+      "name": "ruby"
+    },
     "name": "opbeans-ruby",
     "target": {
       "type": "postgresql"

go.mod

@@ -3,10 +3,10 @@ module github.com/elastic/apm-server
 go 1.20
 
 require (
-	github.com/axiomhq/hyperloglog v0.0.0-20230201085229-3ddf4bad03dc
 	github.com/cespare/xxhash/v2 v2.2.0
 	github.com/dgraph-io/badger/v2 v2.2007.3-0.20201012072640-f5a7e0a1c83b
 	github.com/dustin/go-humanize v1.0.1
+	github.com/elastic/apm-aggregation v0.0.0-20230807142825-c82b2b7e590c
 	github.com/elastic/apm-data v0.1.1-0.20230803060036-9180b59d7888
 	github.com/elastic/beats/v7 v7.0.0-alpha2.0.20230808073125-1fe462c68f7d
 	github.com/elastic/elastic-agent-client/v7 v7.2.0
@@ -15,7 +15,6 @@ require (
 	github.com/elastic/gmux v0.2.0
 	github.com/elastic/go-docappender v0.2.1-0.20230724080315-b714d6181871
 	github.com/elastic/go-elasticsearch/v8 v8.9.0
-	github.com/elastic/go-hdrhistogram v0.1.0
 	github.com/elastic/go-sysinfo v1.11.0
 	github.com/elastic/go-ucfg v0.8.6
 	github.com/go-sourcemap/sourcemap v2.1.3+incompatible
@@ -59,13 +58,21 @@ require (
 )
 
 require (
-	github.com/DataDog/zstd v1.4.4 // indirect
+	github.com/DataDog/zstd v1.4.5 // indirect
 	github.com/Microsoft/go-winio v0.6.1 // indirect
 	github.com/OneOfOne/xxhash v1.2.8 // indirect
 	github.com/Shopify/sarama v1.38.1 // indirect
 	github.com/apache/thrift v0.18.1 // indirect
 	github.com/armon/go-radix v1.0.0 // indirect
+	github.com/axiomhq/hyperloglog v0.0.0-20230201085229-3ddf4bad03dc // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash v1.1.0 // indirect
+	github.com/cockroachdb/errors v1.8.1 // indirect
+	github.com/cockroachdb/logtags v0.0.0-20190617123548-eb05cc24525f // indirect
+	github.com/cockroachdb/pebble v0.0.0-20230627193317-c807f60529a3 // indirect
+	github.com/cockroachdb/redact v1.0.8 // indirect
+	github.com/cockroachdb/sentry-go v0.6.1-cockroachdb.2 // indirect
+	github.com/cockroachdb/tokenbucket v0.0.0-20230613231145-182959a1fad6 // indirect
 	github.com/containerd/containerd v1.7.1 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/dgraph-io/ristretto v0.1.1 // indirect
@@ -106,10 +113,13 @@ require (
 	github.com/joeshaw/multierror v0.0.0-20140124173710-69b34d4ec901 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/compress v1.16.7 // indirect
+	github.com/kr/pretty v0.3.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/magefile/mage v1.15.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.17 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/mitchellh/hashstructure v1.1.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/open-telemetry/opentelemetry-collector-contrib/internal/coreinternal v0.81.0 // indirect
@@ -119,8 +129,12 @@ require (
 	github.com/pierrec/lz4/v4 v4.1.17 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c // indirect
+	github.com/prometheus/client_golang v1.16.0 // indirect
+	github.com/prometheus/client_model v0.4.0 // indirect
+	github.com/prometheus/common v0.44.0 // indirect
 	github.com/prometheus/procfs v0.10.1 // indirect
 	github.com/rcrowley/go-metrics v0.0.0-20201227073835-cf1acfcdf475 // indirect
+	github.com/rogpeppe/go-internal v1.10.0 // indirect
 	github.com/shirou/gopsutil v3.21.11+incompatible // indirect
 	github.com/shirou/gopsutil/v3 v3.23.5 // indirect
 	github.com/shoenig/go-m1cpu v0.1.6 // indirect
@@ -141,7 +155,8 @@ require (
 	go.uber.org/atomic v1.11.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
 	golang.org/x/crypto v0.11.0 // indirect
-	golang.org/x/mod v0.10.0 // indirect
+	golang.org/x/exp v0.0.0-20230713183714-613f0c0eb8a1 // indirect
+	golang.org/x/mod v0.11.0 // indirect
 	golang.org/x/sys v0.10.0 // indirect
 	golang.org/x/text v0.11.0 // indirect
 	golang.org/x/tools v0.9.3 // indirect