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>
evalRollupFuncNoCache() may return time series with identical labels (aka duplicate series)
when performing queries satisfying all the following conditions:
- It must select time series with multiple metric names. For example, {__name__=~"foo|bar"}
- The series selector must be wrapped into rollup function, which drops metric names. For example, rate({__name__=~"foo|bar"})
- The rollup function must be wrapped into aggregate function, which has no streaming optimization.
For example, quantile(0.9, rate({__name__=~"foo|bar"})
In this case VictoriaMetrics shouldn't return `cannot merge series: duplicate series found` error.
Instead, it should fall back to query execution with disabled cache.
Also properly store the merged results. Previously they were incorrectly stored because of a typo
introduced in the commit 41a0fdaf39
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5332
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5337
`version` label won't show the difference if various flavors of the same
version were deployed. But `short_version` will.
For example, on the sandbox env we test VM builds before new version release.
Without this change, the version update won't be visible on dashboard.
Signed-off-by: hagen1778 <roman@victoriametrics.com>