This change switches the remote_write API to use the TSDB WAL. This should reduce memory usage and prevent sample loss when the remote end point is down.
We use the new LiveReader from TSDB to tail WAL segments. Logic for finding the tracking segment is included in this PR. The WAL is tailed once for each remote_write endpoint specified. Reading from the segment is based on a ticker rather than relying on fsnotify write events, which were found to be complicated and unreliable in early prototypes.
Enqueuing a sample for sending via remote_write can now block, to provide back pressure. Queues are still required to acheive parallelism and batching. We have updated the queue config based on new defaults for queue capacity and pending samples values - much smaller values are now possible. The remote_write resharding code has been updated to prevent deadlocks, and extra tests have been added for these cases.
As part of this change, we attempt to guarantee that samples are not lost; however this initial version doesn't guarantee this across Prometheus restarts or non-retryable errors from the remote end (eg 400s).
This changes also includes the following optimisations:
- only marshal the proto request once, not once per retry
- maintain a single copy of the labels for given series to reduce GC pressure
Other minor tweaks:
- only reshard if we've also successfully sent recently
- add pending samples, latest sent timestamp, WAL events processed metrics
Co-authored-by: Chris Marchbanks <csmarchbanks.com> (initial prototype)
Co-authored-by: Tom Wilkie <tom.wilkie@gmail.com> (sharding changes)
Signed-off-by: Callum Styan <callumstyan@gmail.com>
This no longer waits for all of the scrape reload to complete
before getting a list of AMs again.
Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
* Add flag for size based retention
Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>
* Deprecate the old retention flag for a new one.
Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>
* Add ability to take a suffix for size flag
Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>
* Address feedback
Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>
* *: use latest release of staticcheck
It also fixes a couple of things in the code flagged by the additional
checks.
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
* Use official release of staticcheck
Also run 'go list' before staticcheck to avoid failures when downloading packages.
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
Add WALSegmentSize as an option, and the corresponding flag "storage.tsdb.wal-segment-size" to tune the max size of wal segment files.
The addressed base problem is to reduce the disk space used by wal segment files : on a raspberry pi, for instance, we often want to reduce write load of the sd card, then, the wal directory is mounted on a memory (space limited) partition.
the default value of the segment max file size, pushed the size of directory to 128 MB for each segment , which is too much ram consumption on a rasp.
the initial discussion is at https://github.com/prometheus/tsdb/pull/450
* update promlog to latest version
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* Update api tests, fix main setup
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* tidy go.sum
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* revendor prometheus/common
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* only initialize config; use kingpin for remote_storage_adapter
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* actually parse the flags
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* clean up imports
Signed-off-by: Alex Yu <yu.alex96@gmail.com>
* web: added ability to set page title through flag.
Signed-off-by: Andrew Chiu <andrew.chiu2@baesystems.com>
* Reformatted variable names and Flag description for readability.
Signed-off-by: Andrew Chiu <andrew.chiu2@baesystems.com>
* assets_vfsdata.go
Signed-off-by: Andrew Chiu <andrew.chiu2@baesystems.com>
* Flag name changed from web.ui-title to web.page-title
Signed-off-by: Andrew Chiu <andrew.chiu2@baesystems.com>
* make assets
Signed-off-by: Andrew Chiu <andrew.chiu2@baesystems.com>
* Support writing output as json
Oftentimes I'll want to execute something based on
the output from promtool, and supporting json
makes it easy to pull out values with a supporting
tool such as jq.
Signed-off-by: stuart nelson <stuartnelson3@gmail.com>
According to the GoDoc for os.Signal [0]:
> Package signal will not block sending to c: the caller must ensure that
> c has sufficient buffer space to keep up with the expected signal rate.
> For a channel used for notification of just one signal value, a buffer
> of size 1 is sufficient.
[0] https://golang.org/pkg/os/signal/#Notify
Signed-off-by: Lucas Serven <lserven@gmail.com>
* Limit the number of samples remote read can return.
- Return 413 entity too large.
- Limit can be set be a flag. Allow 0 to mean no limit.
- Include limit in error message.
- Set default limit to 50M (* 16 bytes = 800MB).
Signed-off-by: Tom Wilkie <tom.wilkie@gmail.com>
To make local debuging with `go run` easyer moved all files into a
dedicate package `runtime`.
This allows running prometheus just by using `go run main.go` instead of
passing mani files like `go run main.go limits_default.go ...`
Signed-off-by: Krasi Georgiev <kgeorgie@redhat.com>
Sorry, I used GitHub's web-based merge-conflict-resolution editor on
https://github.com/prometheus/prometheus/pull/4308 and it didn't show me
test errors afterwards, but maybe they didn't run again or I should have
waited or something.
Signed-off-by: Julius Volz <julius.volz@gmail.com>
`debug all` - all information
`debug metrics` - metrics information
`debug pprof` - profiling information
the final result is compressed in a `tar.gz` file
Signed-off-by: chyeh <chyeh.taiwan@gmail.com>
Start rule manager only after tsdb and config is loaded.
Stop rule manager before tsdb to avoid writing to closed storage.
Wait for any in-progress reloads to complete before shutting
down rule manager, so that rule manager doesn't get updated after
being shut down.
Remove incorrect comment around shutting down query enginge.
Log when config reload is completed.
Fixes#4133Fixes#4262
Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
This adds a parameter to the storage selection interface which allows
query engine(s) to pass information about the operations surrounding a
data selection.
This can for example be used by remote storage backends to infer the
correct downsampling aggregates that need to be provided.
* refactor: move targetGroup struct and CheckOverflow() to their own package
* refactor: move auth and security related structs to a utility package, fix import error in utility package
* refactor: Azure SD, remove SD struct from config
* refactor: DNS SD, remove SD struct from config into dns package
* refactor: ec2 SD, move SD struct from config into the ec2 package
* refactor: file SD, move SD struct from config to file discovery package
* refactor: gce, move SD struct from config to gce discovery package
* refactor: move HTTPClientConfig and URL into util/config, fix import error in httputil
* refactor: consul, move SD struct from config into consul discovery package
* refactor: marathon, move SD struct from config into marathon discovery package
* refactor: triton, move SD struct from config to triton discovery package, fix test
* refactor: zookeeper, move SD structs from config to zookeeper discovery package
* refactor: openstack, remove SD struct from config, move into openstack discovery package
* refactor: kubernetes, move SD struct from config into kubernetes discovery package
* refactor: notifier, use targetgroup package instead of config
* refactor: tests for file, marathon, triton SD - use targetgroup package instead of config.TargetGroup
* refactor: retrieval, use targetgroup package instead of config.TargetGroup
* refactor: storage, use config util package
* refactor: discovery manager, use targetgroup package instead of config.TargetGroup
* refactor: use HTTPClient and TLS config from configUtil instead of config
* refactor: tests, use targetgroup package instead of config.TargetGroup
* refactor: fix tagetgroup.Group pointers that were removed by mistake
* refactor: openstack, kubernetes: drop prefixes
* refactor: remove import aliases forced due to vscode bug
* refactor: move main SD struct out of config into discovery/config
* refactor: rename configUtil to config_util
* refactor: rename yamlUtil to yaml_config
* refactor: kubernetes, remove prefixes
* refactor: move the TargetGroup package to discovery/
* refactor: fix order of imports
Users are starting to use these mistakenly thinking they'll help
with issues, and thus causing some confusion.
Thus hide them and make it clear that they're only there for testing
reasons.
Currently all read queries are simply pushed to remote read clients.
This is fine, except for remote storage for wich it unefficient and
make query slower even if remote read is unnecessary.
So we need instead to compare the oldest timestamp in primary/local
storage with the query range lower boundary. If the oldest timestamp
is older than the mint parameter, then there is no need for remote read.
This is an optionnal behavior per remote read client.
Signed-off-by: Thibault Chataigner <t.chataigner@criteo.com>
Instead or only printing the help message, which is not always helpful.
For example, when upgrading from prometheus v1, the retention time value
format has changed and now only accepts one unit (e.g. "15d") where it
previously allowed more complex strings (e.g. "360h0m0s").
This commit provides the error message as an explanation for the parsing
failure.
The usage of govalidator is redundant with the call to url.Parse for
url validation. Removing it has the following benefits:
- The explicit error message is displayed instead of just a generic
valid/invalid message
- Slightly smaller code with one fewer external dependency
- Speed improvement by removing duplicate call to url.Parse (inside
govalidator.IsURL()
- Resolves issue #2717
The only potential drawback of removing govalidator is that certain
URLs will be considered valid which were previously invalid. For example:
- URLs with hostnames that start and/or end with an underscore (http://_example.com_)
- URLs with hostnames that contain some special characters (http://foo&*bar.org)
These are valid URIs according to RFC 3986 and valid domain names per RFC 2181,
however they are not valid hostnames per RFC 952.
Whenever a route prefix is applied, the router prepends the prefix to
the URL path on the request. For most handlers, this is not an issue
because the request's path is only used for routing and is not actually
needed by the handler itself. However, Prometheus delegates the handling
of the /debug/* endpoints to the http.DefaultServeMux which has it's own
routing logic that depends on the url.Path. As a result, whenever a
prefix is applied, the prefixed URL is passed to the DefaultServeMux
which has no awareness of the prefix and returns a 404.
This change fixes the issue by creating a new serveDebug handler which
routes requests /debug/* requests to appropriate net/http/pprof handler
and removing the net/http/pprof import in cmd/prometheus since it is no
longer necessary.
Fixes#2183.
* Move fingerprint to Hash()
* Move away from tsdb.MultiError
* 0777 -> 0666 for files
* checkOverflow of extra fields
Signed-off-by: Goutham Veeramachaneni <cs14btech11014@iith.ac.in>
* Print uname on prom startup
* Make uname file linux-only
* Add missing license headers
Add missing license headers
* Print OS when uname is not available
* Print only OS name when uname not available
* Remove extra space, fix cmd/prometheus/main.go license header
* Add fix for int8 and uint8 systems
* Better formatting for build tags in cmd/prometheus/uname files
* Remove newline
This is a fairly easy attempt to dynamically evict chunks based on the
heap size. A target heap size has to be set as a command line flage,
so that users can essentially say "utilize 4GiB of RAM, and please
don't OOM".
The -storage.local.max-chunks-to-persist and
-storage.local.memory-chunks flags are deprecated by this
change. Backwards compatibility is provided by ignoring
-storage.local.max-chunks-to-persist and use
-storage.local.memory-chunks to set the new
-storage.local.target-heap-size to a reasonable (and conservative)
value (both with a warning).
This also makes the metrics intstrumentation more consistent (in
naming and implementation) and cleans up a few quirks in the tests.
Answers to anticipated comments:
There is a chance that Go 1.9 will allow programs better control over
the Go memory management. I don't expect those changes to be in
contradiction with the approach here, but I do expect them to
complement them and allow them to be more precise and controlled. In
any case, once those Go changes are available, this code has to be
revisted.
One might be tempted to let the user specify an estimated value for
the RSS usage, and then internall set a target heap size of a certain
fraction of that. (In my experience, 2/3 is a fairly safe bet.)
However, investigations have shown that RSS size and its relation to
the heap size is really really complicated. It depends on so many
factors that I wouldn't even start listing them in a commit
description. It depends on many circumstances and not at least on the
risk trade-off of each individual user between RAM utilization and
probability of OOMing during a RAM usage peak. To not add even more to
the confusion, we need to stick to the well-defined number we also use
in the targeting here, the sum of the sizes of heap objects.
Currently, if a series stops to exist, its head chunk will be kept
open for an hour. That prevents it from being persisted. Which
prevents it from being evicted. Which prevents the series from being
archived.
Most of the time, once no sample has been added to a series within the
staleness limit, we can be pretty confident that this series will not
receive samples anymore. The whole chain as described above can be
started after 5m instead of 1h. In the relaxed case, this doesn't
change a lot as the head chunk timeout is only checked during series
maintenance, and usually, a series is only maintained every six
hours. However, there is the typical scenario where a large service is
deployed, the deoply turns out to be bad, and then it is deployed
again within minutes, and quite quickly the number of time series has
tripled. That's the point where the Prometheus server is stressed and
switches (rightfully) into rushed mode. In that mode, time series are
processed as quickly as possible, but all of that is in vein if all of
those recently ended time series cannot be persisted yet for another
hour. In that scenario, this change will help most, and it's exactly
the scenario where help is most desperately needed.
Rationale: The default value for GOGC is 100, i.e. a garbage collected
is initialized once as many heap space has been allocated as was in
use after the last GC was done. This ratio doesn't make a lot of sense
in Prometheus, as typically about 60% of the heap is allocated for
long-lived memory chunks (most of which are around for many hours if
not days). Thus, short-lived heap objects are accumulated for quite
some time until they finally match the large amount of memory used by
bulk memory chunks and a gigantic GC cyle is invoked. With GOGC=40, we
are essentially reinstating "normal" GC behavior by acknowledging that
about 60% of the heap are used for long-term bulk storage.
The median Prometheus production server at SoundCloud runs a GC cycle
every 90 seconds. With GOGC=40, a GC cycle is run every 35 seconds
(which is still not very often). However, the effective RAM usage is
now reduced by about 30%. If settings are updated to utilize more RAM,
the time between GC cycles goes up again (as the heap size is larger
with more long-lived memory chunks, but the frequency of creating
short-lived heap objects does not change). On a quite busy large
Prometheus server, the timing changed from one GC run every 20s to one
GC run every 12s.
In the former case (just changing GOGC, leave everything else as it
is), the CPU usage increases by about 10% (on a mid-size referenc
server from 8.1 to 8.9). If settings are adjusted, the CPU
consumptions increases more drastically (from 8 cores to 13 cores on a
large reference server), despite GCs happening more rarely, presumably
because a 50% larger set of memory chunks is managed now. Having more
memory chunks is good in many regards, and most servers are running
out of memory long before they run out of CPU cycles, so the tradeoff
is overwhelmingly positive in most cases.
Power users can still set the GOGC environment variable as usual, as
the implementation in this commit honors an explicitly set variable.
This removes legacy support for specific remote storage systems in favor
of only offering the generic remote write protocol. An example bridge
application that translates from the generic protocol to each of those
legacy backends is still provided at:
documentation/examples/remote_storage/remote_storage_bridge
See also https://github.com/prometheus/prometheus/issues/10
The next step in the plan is to re-add support for multiple remote
storages.
