diff --git a/README.md b/README.md index a8a9487..6e9dff7 100644 --- a/README.md +++ b/README.md @@ -6,25 +6,41 @@ The cc-metric-store provides a simple in-memory time series database for storing metrics of cluster nodes at preconfigured intervals. It is meant to be used as part of the [ClusterCockpit suite](https://github.com/ClusterCockpit). As all data is kept in-memory (but written to disk as compressed JSON for long term -storage), accessing it is very fast. It also provides aggregations over time -_and_ nodes/sockets/cpus. +storage), accessing it is very fast. It also provides topology aware +aggregations over time _and_ nodes/sockets/cpus. There are major limitations: Data only gets written to disk at periodic -checkpoints, not as soon as it is received. +checkpoints, not as soon as it is received. Also only the fixed configured +duration is stored and available. -Go look at the `TODO.md` file and the [GitHub +Go look at the [GitHub Issues](https://github.com/ClusterCockpit/cc-metric-store/issues) for a progress -overview. Things work, but are not properly tested. The -[NATS.io](https://nats.io/) based writing endpoint consumes messages in [this +overview. The [NATS.io](https://nats.io/) based writing endpoint consumes messages in [this format of the InfluxDB line protocol](https://github.com/ClusterCockpit/cc-specifications/blob/master/metrics/lineprotocol_alternative.md). +## Building + +`cc-metric-store` can be built using the provided `Makefile`. +It supports the following targets: + +- `make`: Build the application, copy a example configuration file and generate + checkpoint folders if required. +- `make clean`: Clean the golang build cache and application binary +- `make distclean`: In addition to the clean target also remove the `./var` + folder +- `make swagger`: Regenerate the Swagger files from the source comments. +- `make test`: Run test and basic checks. + ## REST API Endpoints The REST API is documented in [swagger.json](./api/swagger.json). You can explore and try the REST API using the integrated [SwaggerUI web interface](http://localhost:8082/swagger). +For more information on the `cc-metric-store` REST API have a look at the +ClusterCockpit documentation [website](https://clustercockpit.org/docs/reference/cc-metric-store/ccms-rest-api/) + ## Run tests Some benchmarks concurrently access the `MemoryStore`, so enabling the @@ -42,19 +58,14 @@ go test -bench=. -race -v ./... ## What are these selectors mentioned in the code? -Tags in InfluxDB are used to build indexes over the stored data. InfluxDB-Tags -have no relation to each other, they do not depend on each other and have no -hierarchy. Different tags build up different indexes (I am no expert at all, but -this is how i think they work). - -This project also works as a time-series database and uses the InfluxDB line -protocol. Unlike InfluxDB, the data is indexed by one single strictly -hierarchical tree structure. A selector is build out of the tags in the InfluxDB -line protocol, and can be used to select a node (not in the sense of a compute -node, can also be a socket, cpu, ...) in that tree. The implementation calls -those nodes `level` to avoid confusion. It is impossible to access data only by -knowing the _socket_ or _cpu_ tag, all higher up levels have to be specified as -well. +The cc-metric-store works as a time-series database and uses the InfluxDB line +protocol as input format. Unlike InfluxDB, the data is indexed by one single +strictly hierarchical tree structure. A selector is build out of the tags in the +InfluxDB line protocol, and can be used to select a node (not in the sense of a +compute node, can also be a socket, cpu, ...) in that tree. The implementation +calls those nodes `level` to avoid confusion. It is impossible to access data +only by knowing the _socket_ or _cpu_ tag, all higher up levels have to be +specified as well. This is what the hierarchy currently looks like: @@ -68,6 +79,8 @@ This is what the hierarchy currently looks like: - cpu3 - cpu4 - ... + - gpu1 + - gpu2 - host2 - ... - cluster2 @@ -81,42 +94,14 @@ Example selectors: ## Config file -All durations are specified as string that will be parsed [like -this](https://pkg.go.dev/time#ParseDuration) (Allowed suffixes: `s`, `m`, `h`, -...). - -- `metrics`: Map of metric-name to objects with the following properties - - `frequency`: Timestep/Interval/Resolution of this metric - - `aggregation`: Can be `"sum"`, `"avg"` or `null` - - `null` means aggregation across nodes is forbidden for this metric - - `"sum"` means that values from the child levels are summed up for the parent level - - `"avg"` means that values from the child levels are averaged for the parent level - - `scope`: Unused at the moment, should be something like `"node"`, `"socket"` or `"hwthread"` -- `nats`: - - `address`: Url of NATS.io server, example: "nats://localhost:4222" - - `username` and `password`: Optional, if provided use those for the connection - - `subscriptions`: - - `subscribe-to`: Where to expect the measurements to be published - - `cluster-tag`: Default value for the cluster tag -- `http-api`: - - `address`: Address to bind to, for example `0.0.0.0:8080` - - `https-cert-file` and `https-key-file`: Optional, if provided enable HTTPS using those files as certificate/key -- `jwt-public-key`: Base64 encoded string, use this to verify requests to the HTTP API -- `retention-on-memory`: Keep all values in memory for at least that amount of time -- `checkpoints`: - - `interval`: Do checkpoints every X seconds/minutes/hours - - `directory`: Path to a directory - - `restore`: After a restart, load the last X seconds/minutes/hours of data back into memory -- `archive`: - - `interval`: Move and compress all checkpoints not needed anymore every X seconds/minutes/hours - - `directory`: Path to a directory +You find the configuration options on the ClusterCockpit [website](https://clustercockpit.org/docs/reference/cc-metric-store/ccms-configuration/). ## Test the complete setup (excluding cc-backend itself) There are two ways for sending data to the cc-metric-store, both of which are supported by the [cc-metric-collector](https://github.com/ClusterCockpit/cc-metric-collector). -This example uses Nats, the alternative is to use HTTP. +This example uses NATS, the alternative is to use HTTP. ```sh # Only needed once, downloads the docker image diff --git a/TODO.md b/TODO.md deleted file mode 100644 index 8c1a36d..0000000 --- a/TODO.md +++ /dev/null @@ -1,51 +0,0 @@ -# Possible Tasks and Improvements - -Importance: - -- **I** Important -- **N** Nice to have -- **W** Won't do. Probably not necessary. - -- Benchmarking - - Benchmark and compare common timeseries DBs with our data and our queries (N) -- Web interface - - Provide simple http endpoint with a status and debug view (Start with Basic - Authentication) -- Configuration - - Consolidate configuration with cc-backend, remove redundant information - - Support to receive configuration via NATS channel -- Memory management - - To overcome garbage collection overhead: Reimplement in Rust (N) - - Request memory directly batchwise via mmap (started in branch) (W) -- Archive - - S3 backend for archive (I) - - Store information in each buffer if already archived (N) - - Do not create new checkpoint if all buffers already archived (N) -- Checkpoints - - S3 backend for checkpoints (I) - - Combine checkpoints into larger files (I) - - Binary checkpoints (started in branch) (W) -- API - - Redesign query interface (N) - - Provide an endpoint for node health based on received metric data (I) - - Introduce JWT authentication for REST and NATS (I) -- Testing - - General tests (I) - - Test data generator for regression tests (I) - - Check for corner cases that should fail gracefully (N) - - Write a more realistic `ToArchive`/`FromArchive` Tests (N) -- Aggregation - - Calculate averages buffer-wise as soon as full, average weighted by length of buffer (N) - - Only the head-buffer needs to be fully traversed (N) - - If aggregating over hwthreads/cores/sockets cache those results and reuse - some of that for new queries aggregating only over the newer data (W) -- Core functionality - - Implement a health checker component that provides information to the web - interface and REST API (I) - - Support units for metrics including to request unit conversions (I) -- Compression - - Enable compression for http API requests (N) - - Enable compression for checkpoints/archive (I) -- Sampling - - Support data re sampling to reduce data points (I) - - Use re sampling algorithms that preserve min/max as far as possible (I) diff --git a/api/swagger.json b/api/swagger.json index 08522ca..9024d5c 100644 --- a/api/swagger.json +++ b/api/swagger.json @@ -24,7 +24,7 @@ "ApiKeyAuth": [] } ], - "description": "Write metrics to store", + "description": "This endpoint allows the users to print the content of", "produces": [ "application/json" ], @@ -81,6 +81,7 @@ "ApiKeyAuth": [] } ], + "description": "This endpoint allows the users to free the Buffers from the", "produces": [ "application/json" ], @@ -136,7 +137,7 @@ "ApiKeyAuth": [] } ], - "description": "Query metrics.", + "description": "This endpoint allows the users to retrieve data from the", "consumes": [ "application/json" ], diff --git a/api/swagger.yaml b/api/swagger.yaml index b14ba8a..a06e2f7 100644 --- a/api/swagger.yaml +++ b/api/swagger.yaml @@ -106,7 +106,7 @@ info: paths: /debug/: post: - description: Write metrics to store + description: This endpoint allows the users to print the content of parameters: - description: Selector in: query @@ -142,6 +142,7 @@ paths: - debug /free/: post: + description: This endpoint allows the users to free the Buffers from the parameters: - description: up to timestamp in: query @@ -178,7 +179,7 @@ paths: get: consumes: - application/json - description: Query metrics. + description: This endpoint allows the users to retrieve data from the parameters: - description: API query payload object in: body diff --git a/internal/api/api.go b/internal/api/api.go index 6e5968c..802b558 100644 --- a/internal/api/api.go +++ b/internal/api/api.go @@ -127,7 +127,10 @@ func (data *ApiMetricData) PadDataWithNull(ms *memorystore.MemoryStore, from, to // handleFree godoc // @summary // @tags free -// @description +// @description This endpoint allows the users to free the Buffers from the +// metric store. This endpoint offers the users to remove then systematically +// and also allows then to prune the data under node, if they do not want to +// remove the whole node. // @produce json // @param to query string false "up to timestamp" // @success 200 {string} string "ok" @@ -182,9 +185,9 @@ func handleFree(rw http.ResponseWriter, r *http.Request) { } // handleWrite godoc -// @summary Receive metrics in line-protocol +// @summary Receive metrics in InfluxDB line-protocol // @tags write -// @description Receives metrics in the influx line-protocol using [this format](https://github.com/ClusterCockpit/cc-specifications/blob/master/metrics/lineprotocol_alternative.md) +// @description Write data to the in-memory store in the InfluxDB line-protocol using [this format](https://github.com/ClusterCockpit/cc-specifications/blob/master/metrics/lineprotocol_alternative.md) // @accept plain // @produce json @@ -245,7 +248,9 @@ type ApiQuery struct { // handleQuery godoc // @summary Query metrics // @tags query -// @description Query metrics. +// @description This endpoint allows the users to retrieve data from the +// in-memory database. The CCMS will return data in JSON format for the +// specified interval requested by the user // @accept json // @produce json // @param request body api.ApiQueryRequest true "API query payload object" @@ -383,7 +388,8 @@ func handleQuery(rw http.ResponseWriter, r *http.Request) { // handleDebug godoc // @summary Debug endpoint // @tags debug -// @description Write metrics to store +// @description This endpoint allows the users to print the content of +// nodes/clusters/metrics to review the state of the data. // @produce json // @param selector query string false "Selector" // @success 200 {string} string "Debug dump" diff --git a/internal/api/docs.go b/internal/api/docs.go index 84cec70..e290e0b 100644 --- a/internal/api/docs.go +++ b/internal/api/docs.go @@ -30,7 +30,7 @@ const docTemplate = `{ "ApiKeyAuth": [] } ], - "description": "Write metrics to store", + "description": "This endpoint allows the users to print the content of", "produces": [ "application/json" ], @@ -87,6 +87,7 @@ const docTemplate = `{ "ApiKeyAuth": [] } ], + "description": "This endpoint allows the users to free the Buffers from the", "produces": [ "application/json" ], @@ -142,7 +143,7 @@ const docTemplate = `{ "ApiKeyAuth": [] } ], - "description": "Query metrics.", + "description": "This endpoint allows the users to retrieve data from the", "consumes": [ "application/json" ],