* app/vmagent: allow to disabled on-disk queue
Previously, it wasn't possible to build data processing pipeline with a
chain of vmagents. In case when remoteWrite for the last vmagent in the
chain wasn't accessible, it persisted data only when it has enough disk
capacity. If disk queue is full, it started to silently drop ingested
metrics.
New flags allows to disable on-disk persistent and immediatly return an
error if remoteWrite is not accessible anymore. It blocks any writes and
notify client, that data ingestion isn't possible.
Main use case for this feature - use external queue such as kafka for
data persistence.
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2110
* adds test, updates readme
* apply review suggestions
* update docs for vmagent
* makes linter happy
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Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
Tests showed that importing a single line with 70MB size takes 5.3GiB
RSS memory for VictoriaMetrics single-node.
In the scenario when user exports and imports data from one VM to another,
it could possibly lead to OOM exception for destination VM.
Importing a single line with 16MB size taks 1.3GiB RSS memory.
Hence, the limit for `import.maxLineLen` was decreased from 100MB to 10MB
to improve reliability of VictoriaMetrics during imports.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
The default caching for Go artifacts from actions/setup-go@v4 uses the hash of go.sum file
as a cache key - see https://github.com/actions/cache/blob/main/examples.md#go---modules .
This isn't enough for VictoriaMetrics case, since different makefile actions build different the Go artifacts,
which need to be cached. So embed the action name in the cache key.
This case is possible after the following steps:
1. vmagent successfully performed handshake with the -remoteWrite.url and the remote storage supports zstd-compressed data.
2. remote storage became unavailable or slow to ingest data, vmagent compressed the collected data into blocks with zstd and puts these blocks to persistent queue on disk.
3. vmagent restarts and the remote storage is unavailable during the handshake, then vmagent falls back to Snappy compression.
4. vmagent starts sending zstd-compressed data from persistent queue to the remote storage, while falsely advertizing it sends Snappy-compressed data.
5. The remote storage receives zstd-compressed data and fails unpacking it with Snappy.
The solution is the same as 12cd32fd75, just fall back to zstd decompression if Snappy decompression fails.
Previously the number of memory allocations inside copyTimeseriesShallow() was equal to 1+len(tss)
Reduce this number to 2 by pre-allocating a slice of timeseries structs with len(tss) length.
The `path!="/favicon.ico"` filter has little sense, since there are many other special paths,
which may be filtered out - /metrics, /flags, /health, /ping, /robots.txt, /-/healthy, /-/ready, /reload, etc.
See /lib/httpserver/httpserver.go for more details.
It will be hard or impossible to maintain filters for all these paths, so it is better to drop this filter
in order to simplify queries and improve the consistency of these queries.
The buffered connection could have exceeded the underlying connection
deadline during reading or writing to an internal buffer.
With this change, buffered connection struct additionally checks
for a deadline in Read/Write methods.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
