Prometheus delete wal files

Prometheus delete wal files. This issue can affect any Prometheus deployment but for our example resolution we are using the default Prometheus Addon that ships with Konvoy 1. when i checked gitlab/prometheus/data/wal consuming more space . max_wal_size (default 1GB): set it higher than the amount of WAL that is written withing one hour to match the checkpoint_timeout setting. retention. You could delete the docker volume: docker volume ls # see what is the actual volume name docker volume rm prometheus_data # or the actual volume name. If you need to use a service discovery system that is not currently supported, your use case may be best served by Prometheus' file-based service discovery mechanism, which enables you to list scrape targets in a JSON file (along with metadata about those Jul 12, 2022 · Hey I am currently trying to configure the scrape config of a prometheus agent to gather all pods in a cluster, all I really care about is tracking cpu and memory right now but other metrics don't hurt. 7 introduced an option for size-based retention with --storage. Thanks for that! you could delete the contents of the WAL directory to unblock Feb 7, 2018 · to Prometheus Developers. 3 Describe the bug When booting up the thanos sidecar with a bucket configuration defined, thanos throws a WAL dir is not accessible. High-traffic servers may retain more than three WAL files in order to keep at least Aug 4, 2018 · 1. Environment. yml as the user that launches the container. 000000, 000001, 000002, etc. What did you do? Reboot host running Prometheus. Since the old file has a larger index number, it would be selected. 0 Jul 28, 2020 · Monitoring system Prometheus has recently hit version 2. These settings have to be made on the primary server, where WAL is Firstly the admin API is not enabled by default in Prometheus 2. This doesn't apply to self-signed root certificates. For each entry in a file: - The type of the entry ( [write] or [delete-bucket-range] ) - The formatted entry contents. I would suggest you to keep a backup of all the WAL which exists currently before doing it as it's possible to recover data from it and backfill with some effort. 2. influxd inspect verify-wal. Kill prometheus process or wait for it to restart. [CHANGE] TSDB: Delete *. 20, improving the CNCF project’s service discovery, query language, and user interface, amongst other things. Metrics are sent over the network using the Prometheus Remote Write protocol. If no custom instance is provided on exporter startup, the DefaultCollectorRegistry. I'm doing: May 25, 2023 · Prometheus keeps the current block of incoming samples in memory and stores them in write-ahead log files, called WAL files, to protect data from loss in case of a crash or restart. Feb 8, 2022. Namely, compression of the write-ahead-log Prometheus can be configured as a receiver for the Prometheus remote write protocol. How it looks on disk The WAL is stored as a sequence of numbered files with 128MiB each by default. . after stoping and deleting the container. Upon restart, Loki will “replay” all of the data in the Apr 13, 2020 · For the 100k samples/s Prometheus that's around 26GB of data, or around 10% of the size the blocks take for the default 2 week retention period. ballok@sap. ExecStart=/apps/prometheus > Generally, Prometheus 2. Sep 9, 2022 · pg_wal is the directory that contains the primary WAL files, and there will never be a *. Oct 18, 2022 · Through Gitlab's API I wrote a code to delete everything but sometimes seems not to be the best method. A segment is written to in pages of 32KB. If I execute a shell inside the container, the working directory is /prometheus and it contains the wal directory, but it does not have the structure mentioned in the documentation and I can not find any metric data. tmp WAL files when Prometheus starts. Look in the meta. its having data of 3 months . Feb 18, 2019 · Write-ahead logging (WAL) is a common practice among modern time series databases — Prometheus uses WAL, InfluxDB uses WAL, TimescaleDB transiently uses WAL from PostgreSQL, Cassandra also uses WAL. /data folder described in Storage section pf Prometheus Documentation. Is this cause the this error? But after that, the compaction was still suceessed once, then continued failed, until now. ), the configuration file defines everything related to scraping jobs and their instances, as well as which rule files to load It also automatically generates monitoring target configurations based on familiar Kubernetes label queries. HeadSeriesRef) bool, mint int64) (* CheckpointStats, error) Checkpoint creates a compacted checkpoint of segments in range [from, to] in the given WAL. [CHANGE] promtool: Add new flag --lint (enabled by default) for the commands check rules and check config, resulting in a new exit code ( 3) for linter errors. 04 with GitLab CE 11. May 26, 2020 · You have a corrupted WAL file which is preventing the Head block compaction, hence WAL is not getting truncated. This property To quickly check whether a rule file is syntactically correct without starting a Prometheus server, you can use Prometheus's promtool command-line utility tool: promtool check rules /path/to/example. 33. com> Co-authored-by: Istvan Zoltan Ballok <istvan. From looking at How to parse Prometheus data as well as the godocs for prometheus, I'm able to read in the file, but I don't know how to Prometheus is configured via command-line flags and a configuration file. I found if prometheus server successfully replay WAL files, it immediately remove series (no idea why) Dec 30, 2019 · If I read the definition of a storage block correctly: it is the max size of a collection of metrics (a block), excluding WAL and compaction files. 0 release Delete account SSH keys Add files and make changes Tutorial: Update Git commit messages GitLab Prometheus metrics IP allowlist endpoints Node exporter Stackhero offers a ready-to-use Prometheus cloud solution: Alert Manager included to send alerts to Slack, Mattermost, Pagerduty, etc. These files contain raw data that has not yet been compacted; thus they are significantly larger than regular block files. 1. Without --find-duplicates, the command outputs the following for each file: The file name. 29. A WAL file here is called a "segment". conf with a restore_command to do so. Write-ahead log files are stored in the 'wal' directory in 128MB data segments. Appender send samples and series directly to the wal. 2. influxd inspect dump-wal. 4 Co-authored-by: Wesley Bermbach <wesley. What did you expect to see? Normal operation. Oct 2, 2021 · Loading the WAL is an integral part of starting Prometheus. Otherwise, you would lose data that had not yet been persisted on shutdown. Multiple prometheus. However, when the prometheus process was resumed, it could lead to: (1), data loss, due to manually remove WAL files Nov 27, 2022 · Here's how you can do it. Something that we should know is that Prometheus follows TSDB format for structuring its files. Next plans: add/remove Kepler to investigate block creating in TSDB; separate this kind of metrics to second Prometheus instance (mid-term) remove PVC from Prometheus, set retention to 2h, extend service with Thanos storage backend May 29, 2020 · I recently inherited a GitLab Omnibus instance in a Docker container. ls to check what is current checkpoint. 12. For each of these blocks we have an index, which will determine in what chunk can we find the time series we’re looking for. If you clear out WAL archives without creating a new BASE, then you will be in trouble when you try to restore your database (via PITR) from them. 2 hour chunk has 19MB (should be around 4. false--agent Using remote write increases the memory footprint of Prometheus. To see the full list of changes, check out the Prometheus 2. By default the HTTP listen address is used for this URL. While the command-line flags configure immutable system parameters (such as storage locations, amount of data to keep on disk and in memory, etc. Otherwise, just wait. Below are the two steps for single compaction to take place. bermbach@sap. If you've played around with remote_write however, you'll need to clear the long-term storage solution which will vary depending on which storage solution it is. size and --storage. Deleting a WAL segment permanently deletes the stored metric values from the time period that the segment covers from Prometheus. TSDB blocks are automatically cleaned up, but it does this on the 2 hour block management schedule. gitlab. This issue happened on our Dev platform, so not a huge impact, but for our production grade platforms deleting WAL is less acceptable. 6. Delete Time Series Metrics. In prometheus-net there is one implementation, named DefaultCollectorRegistry. 30. Jan 12, 2021 · 1. Instance singleton is used. If you are going to delete WAL files, then you need to make sure you have a valid base to build from again Nov 28, 2020 · Before that, due to out of disk space, it failed when “write to WAL”. Each run, it should read some prometheus metrics from a file, run its logic, update a success/fail counter, and write metrics back out to a file. wal-compression flag. All the incoming data must be Sep 12, 2018 · To enabled it, pass --web. query-url which is used in the user interface for rules/alerts pages. Nov 30, 2021 · I am having issues with WAL directory. All groups and messages Prometheus offers a variety of service discovery options for discovering scrape targets, including Kubernetes, Consul, and many others. Sep 2, 2020 · Our solution was tainting the node then rolling the Prometheus pod to a new node. This resets the data set to an May 12, 2022 · Service Discovery. Is this dir a T Dec 1, 2021 · My guess is that prometheus is failing to update the main database from the WAL, and if so will probably be logging some message saying what it's stuck on. Also it might depend on whether a big portion of the used diskspace is used by WAL files, as the documentation mentioned these are not compacted yet and Oct 28, 2020 · Apparently Prometheus Docker is using the user nobody, setting folder permissions to nogroup worked for me: chgrp -R nogroup /mnt/prometheus So in your Ansible playbook: - name: fix permissions for prometheus mnt folder file: path: '/mnt/prometheus' group: nogroup recurse: yes become: yes Prometheus is configured via command-line flags and a configuration file. Then, if an ingester happens to crash, it can replay these events on the disk and restore the in-memory state that it had before crashing. The influxd inspect verify-wal command analyzes the Write-Ahead Log (WAL) to check if there are any corrupt files. #4847 Query: add --alert. As of Prometheus 2. 6MB=1. json in the TSDB block directories. We are using Prometheus 2. Aug 20, 2021 · There is no safe way to manually remove files in pg_wal. What you can delete are archived WAL files as written by archive_command or pg_receivewal. We use the Prometheus WAL package to manage writing and reading these events on the In the event of a crash, there could be data loss. Nov 25, 2019 · I think prometheus should only replay the WAL files winthin 2 hours. Jan 15, 2020 · I have a Prometheus server running, on it's own node in GCP, with the following specs: 8 CPU, 32 GB MEM and 100 GB SSD. WAL files contain raw data that has not yet been compacted. Nov 9, 2022 · Logger, w * WAL, from, to int, keep func(id chunks. A stale replication slot? Is the archiver stuck? Is wal_keep_size (wal_keep_segments in older releases) large? Once you have fixed the problem, the situation will gradually improve. These configurations allow users to define the maximum size and age of data that should be retained in the Prometheus database. Prometheus does not start. Also, I have to delete the metrics database from Prometheus. I've a go application that gets run periodically by a batch. Tapping into log data can provide vital monitoring visibility. Config details: - '--web. What did you expect to see? Out-of-disk errors should cause temporary loss of data but not a fatal condition I have to log in and delete the WAL to fix. 1 and we are scraping just relatively few metrics (~30k once per minute). This should roughly half the size of the WAL, at the cost of some additional CPU Apr 1, 2022 · Let’s assume we decided that we want to drop prometheus_http_request_duration_seconds_bucket & prometheus_http_response_size_bytes_bucket metric, as it’s of no practical use to us. The influxd inspect dump-wal command outputs data from WAL files for debugging purposes. It might also indicate that you are using an unsupported file system, Oct 28, 2021 · It will initialize it on startup if it doesn't exist so simply clearing its content is enough. Data retention is configured for 1 hour. Solution. This is where the powerful combination of Prometheus and grok_exporter comes in. Every minute we initiate a compaction cycle where we check for step-1 and only proceed to step-2 if step-1 was not empty. yml The promtool binary is part of the prometheus archive offered on the project's download page. WriteTo, bypassing WAL entirely (this issue) prometheus. 64384. 8. thanks a lot for the reply ! i increased it to 64,000 and on checking open files using lsof i get an output of around 36,000, it seems 64k should be enough but still getting that error, prometheus2 ~]$ sudo lsof | wc -l. The write ahead log operates in segments that are numbered and sequential, e. Your only "solution" is to delete the WAL (rm -r data/wal), but that would entail losing some of your data. Recovering without archived WAL Sep 12, 2020 · to Johny, Prometheus Users. You probably just need to wait for the maxTime on the oldest block to expire. Which means you have to have a BASE to start off of before you can apply any WAL Files. g. The only way to recover for now is to delete /appdata/cpro/prometheus/wal/00000174 (and any other WAL files which it says is corrupted). This is still a bit best effort though as it does not (yet) include the space taken by the WAL or blocks being populated by compaction. This must be made active by starting the server with the option--web. For example, after deleting everything, I get "ghost users", or can't create a user with a name that already existed on a previous run. Let’s look into WAL theory. 3 The Feb 9, 2022 · Loki Compactor error "failed to upload delete requests file" err="mkdir index: read-only file system" The main question is, how many WAL files is it having to replay at startup? I've seen some servers get into bad crash / recovery loops where they generate many hundreds of files in the wal dir. 0. 25890. @gouthamve Deleting the wal files allowed prometheus to come back online. There is a Prometheus installed in Kubernetes Azure AKS with default storage StandardSSD. For each series in the WAL, the remote write code caches a mapping of series ID to label values, causing large amounts of series churn to significantly increase memory usage. Looking forward to your reply！. 47. In this comprehensive guide, you‘ll learn how to leverage Prometheus for monitoring and alerting on your log files. size, that is specifying a maximum amount of disk space used by blocks. This means it needs the ability to map virtual pages to the data on disk. RemoveLabelled(), you can simply clear all registrations by using DefaultCollectorRegistry. After a clean startup, Prometheus should cleanup this situation. It might be that there are multiple blocks. Clear(). Mar 15, 2019 · 2019-03-15 14:48:45,762 INFO exited: prometheus (exit status 1; not expected) The repair. robustperception. Bug Report. This means there is only 4GiB available for both running memory, and storage. May 3, 2022 · welcome to the community @dlgs!. But, there is a kernel / user split, so even if you have 4GiB of virtual memory Nov 21, 2022 · Prometheus uses the index number in the filename (the number after the first dot) to determine which file is the newest, rather than the age of the file. time: Number of days to store the metrics by default to 15d. http-client-file flag for sidecar to connect Prometheus with basic auth or TLS. 0 and I have gone through the same issue in forums. Dec 4, 2019 · You would have to (1) Bring down the Prometheus server (2) Delete the WAL (3) Start again - but you would lose a lot of data given how long the data was not compacted from Head. The memory usage is increasing, as the WAL segments is loaded. Only check the config file syntax, ignoring file and content validation referenced in the config--lint: Linting checks to apply to the rules specified in the config. As an alternative to . Available options are: all, duplicate-rules, none. May 25, 2022 · Start () Stop () } This would open the door for some interesting implementations: Watch the WAL on disk as it does today (the default implementation) Have Prometheus Agent's storage. In addition to Prometheus and Alertmanager, OpenShift Container Platform Monitoring also includes node-exporter and kube-state-metrics. Could be an option to investigate the WAL files, tried with ldb dump_walfrom rocksdb-tool package without success. And hence the WAL just keeps growing as new data is scraped. Prometheus version v2. All series not satisfying keep, samples/tombstones/exemplars below mint and metadata that Jun 19, 2020 · This had an impact on our server startup times since it loads all files on it to find out if it has to keep appending metrics the previous partial WAL blocks or create new ones. And the worse part are WAL files, each having ~256MB (server is running for Apr 29, 2020 · With WAL, whenever an ingester gets a write request, it logs this event into a file along with storing it in the memory. The text was updated successfully, but these errors were encountered: Oct 24, 2023 · Ran Prometheus. now its 281 GB. The lost+found directory is usually created by the OS. backup file in it. We write a Tombstones record into the WAL before processing the delete request. Maximum size of data on the volume is about 500Mb. Don't do it. 7 and 2. Sep 26, 2023 · 1. Recovering with archived WAL. WAL is used as a protection against losing of recently added data on power loss. We would like to show you a description here but the site won’t allow us. My GitLab config: Aug 3, 2021 · hi, our gitlab server is getting filled in quick time. Prometheus version: 2. cd to wal directory. For example, if the grafana server wasn’t shut down cleanly the filesystem would write parts of the files that were open at that time to be potentially recovered later. 3B advertised by documentation). Always back up your Prometheus data first. The volume storage size is 1 Gb. When the file is syntactically valid, the Jun 9, 2022 · To reduce the rate of checkpoints, change these parameters: checkpoint_timeout (default 5 minutes): set it to something high like 1 hour. Dec 13, 2022 · 0. WAL:msg="compaction failed" err="head truncate failed (in compact): create checkpoint: read segments: corruption #7255 Handle Corrupt Prometheus Write-Ahead Log (WAL) As a last resort, you can delete corrupt WAL segments (files and directories) directly on the Prometheus persistent volume (PV). If you kept the archived WAL somewhere else, you might just be able to copy the files back into pg_xlog, or create a recovery. Normally the files are reserved for only two hours. 30, such as improving WAL load memory usage by 24% and CPU usage by 19%, adding two more optional per-scrape metrics (scrape_timeout_seconds and scrape_sample_limit) in addition to up and friends, and more. I am using Prometheus version 2. It is not suitable for replacing the ingestion via scraping and turning Prometheus into a push-based metrics collection system. What did you see instead? Under which circumstances? In production#5998 (closed) we started seeing Prometheus servers being OOM killed, upon further investigation, we see that there is a large WAL file and chunks_head because WAL failed to flush. Drop# In order to drop the above-mentioned metrics, we need to add metric_relabel_configs in Prometheus scrape config with the metric name we need to drop : When restarted it, it failed to restart (or took a quite a long time to restart) due to too many WAL files to be replayed, and consumed too much memory. Apr 18, 2021 · The problem is likely the 32-bit OS. The Write Ahead Log (WAL) helps fill this gap in reliability. Blocks also must be fully expired (maxTime) before they are deleted. I run a basic Prometheus Docker container prom/prometheus on Kubernetes. Use the following syntax to delete all time series metrics that match some label: #4612 Sidecar: add --prometheus. #10435. go loop continued until I deleted the contents of WAL (as suggested in other issues). tsdb. The main change the Prometheus team wanted to put front and centre was a new default in the system’s time series database (TSDB). The main properties that you can configure are the following ones: storage. It was a disk issue of the AKS that if you checked the condition of the node, it would say ReadonlyFilesystem . Prometheus will retain a minimum of three write-ahead log files. So tight that I cant even create backups. 2 Metrics endpoint mapped to a service is exposed by the service to a service monitor. Its getting tight with space on there. We‘ll cover: The … Monitoring Your Log . With --find-duplicates, the command outputs the following for This doesn't apply to self-signed root certificates. to update / create new checkpoint create new checkpoint directory with incremented segment file number. zoltan. Use --lint=none to disable linting: duplicate-rules--lint-fatal: Make lint errors exit with exit code 3. My question is how wal files grow. com shows the configuration which disable the feature, we dont want it (prometheus[‘enable’] = false May 28, 2020 · I am searching for the . Dedicated email server to send unlimited email alerts; Blackbox to probe HTTP, ICMP, TCP, and more; Easy configuration with online configuration file editor; One-click updates for easy maintenance Jan 12, 2023 · After the prometheus service ran for a period of time, the number of wal directory files increased continuously, with one file every minute and sometimes tens of thousands of files, which directly affected the restart time of the prometheus service. Prometheus uses mmap and virtual memory to manage access to the stored data. It has been mentioned that it was fixed in version 2. It includes the most recent checkpoint if it exists. Off course this means you will lose those data answered Mar 12 at 12:55. io. time configurations. #10317. Unfortunately, this is known to be resource-intensive and takes a while. 26. #4856 Mixin: Add Query Frontend Grafana dashboard. Aug 11, 2020 · Which chart: bitnami/prometheus-operator @ 0. Oct 28, 2020 · I can browse the mounted filesystem on my docker host (a Raspberry Pi 4), touch files and read prometheus. What did you see instead? Under which circumstances? The disk filled up, and the first report of this was from the WAL: The --find-duplicates flag determines the influxd inspect dump-wal output. You have to figure out the reason that keeps PostgreSQL from deleting the files. enable-admin-api Dec 27, 2023 · Log files contain a wealth of operational intelligence about your systems and applications. When Prometheus get's above 15 GB in data, then when the node restarts, Prometheus get's OOM Killed, and i can see that it's using all the memory on the node. Exec to prometheus pod. Feb 5, 2023 · As you can see, Prometheus groups data in blocks of 2 hours, keeping the current data in a WAL file. remote_write components can be specified by giving them different labels. Mar 12, 2021 · www. Therefore, could only manually remove some WAL files to restore it again. Mar 28, 2023 · Prometheus is a powerful monitoring system that provides a simple solution to the retention of old data with --storage. If you restart Prometheus, it tries to load the entire WAL into memory. also, can i delete the existing data in the folder ps: docs. Dec 17, 2021 · Additional motivation: We observed the symptoms of prometheus/prometheus#10043 which is expected to be fixed by prometheus/prometheus#10316 based on this comment: prometheus/prometheus#10406 (comment) since v2. Sep 14, 2021 · There are a lot of other smaller improvements in Prometheus 2. 11 but for me, the WAL files are not deleting even though I use version 2. rules. http-client and --prometheus. Use it with caution for specific low-volume use cases. ), the configuration file defines everything related to scraping jobs and their instances, as well as which rule files to load As of Prometheus 2. i need configurations in gitlab. 0 there's also WAL compression, which you can enable with the --storage. Most users report ~25% increased memory usage, but that number is dependent on the shape of the data. Cool Tip: Install Prometheus using Docker on Ubuntu and CentOS! Read More →. We noticed that our disk consumption is quite high (much higher than 1. 12 is quite old, consider upgrading to the latest > version – there have been lots of WAL related improvements since then. rb file to reduce keep only 10 days data . So, for example WAL is 61GB, and memory is 32GB, so Prometheus keeps on restarting when it gets killed by the OOM, as it consumes the whole server memory of 24 GB. The root cause was because of a curropted WAL file . , and are limited to 128MB by default. I have the tsdb retention size to 175 GB, but the WAL size is increasing huge. 3*30k*2*60). Prometheus WAL files are not deleted since the Prometheus setup was done. The WAL in Grafana Loki records incoming data and stores it on the local file system in order to guarantee persistence of acknowledged data in the event of a process crash. server: I have an issue with Prometheus, where the . If you want to reset its configuration, delete /etc/prometheus and reinstall the package. remote_write collects metrics sent from other components into a Write-Ahead Log (WAL) and forwards them over the network to a series of user-supplied endpoints. All groups and messages Sep 26, 2023 · 1. com> So with that in mind, it seems that we should probably add some option (env var, cli flag) to allow for partial WAL files -- otherwise if any file is corrupt the only way to get prometheus to start is to delete them all or manually rename all the files. This is not considered an efficient way of ingesting samples. First identify the Persistent Volume associated Jul 27, 2021 · Merging these overlapping blocks avoid the need for deduplication. wal file is taking up almost all the ressources. Only the last page of the most recent segment may be partial. Node-exporter is an agent deployed on every node to collect metrics about it. 11. I am running a server on Ubuntu 18. prometheus2 ~]$ ulimit -Hn. The compaction cycle runs these steps in a loop and exits when step-1 is empty. enable-admin-api flag to Prometheus through start-up script or docker-compose file, depending on installation method. The solution is to identify the PV that Prometheus Server is using, and then delete the chunk file mentioned in the Prometheus Pod logs. 1 Metrics endpoint exposed by a running application in a pod is mapped to a service. See sample screenshot added below (click on image if its loaded very small) Sep 15, 2023 · Root cause is that the WAL folder is not getting cleaned by default. A WAL record is an opaque byte slice that gets split up into sub-records Jan 24, 2022 · Write-ahead log files are stored in the wal directory in 128MB segments. 8 there's new flags and options. Sep 26, 2020 · We store something called "tombstones" which indicates the deleted series and time range of deletion. Share But you should never delete WAL segments by hand. Assuming you are talking about WAL archives, you can delete everything before (but not including) 000000010000000000000096 if you don't need to WAL Disk Format. See the manual on PITR and log shipping for details. enable-admin-api'. pv ow tl id tk ym qw yg bd vi