From 8d99e94a522ac50f67de21df7573294004356ee9 Mon Sep 17 00:00:00 2001 From: Aliaksandr Valialkin Date: Tue, 13 Jul 2021 15:48:25 +0300 Subject: [PATCH] docs: clarify why spare CPU and RAM resources are needed in `capacity planning` --- README.md | 6 +++--- docs/Cluster-VictoriaMetrics.md | 6 +++--- docs/README.md | 6 +++--- docs/Single-server-VictoriaMetrics.md | 6 +++--- 4 files changed, 12 insertions(+), 12 deletions(-) diff --git a/README.md b/README.md index c925904d3..95d2e95bd 100644 --- a/README.md +++ b/README.md @@ -1106,10 +1106,10 @@ VictoriaMetrics capacity scales linearly with the available resources. The neede The needed storage space for the given retention (the retention is set via `-retentionPeriod` command-line flag) can be extrapolated from disk space usage in a test run. For example, if `-storageDataPath` directory size becomes 10GB after a day-long test run on a production workload, then it will need at least `10GB*100=1TB` of disk space for `-retentionPeriod=100d` (100-days retention period). -It is recommended leaving the following amounts of spare resources for reducing the probability of issues related to temporary spikes in the workload: +It is recommended leaving the following amounts of spare resources: -* 50% of free RAM -* 50% of spare CPU +* 50% of free RAM for reducing the probability of OOM (out of memory) crashes and slowdowns during temporary spikes in workload. +* 50% of spare CPU for reducing the probability of slowdowns during temporary spikes in workload. * At least 30% of free storage space at the directory pointed by `-storageDataPath` command-line flag. diff --git a/docs/Cluster-VictoriaMetrics.md b/docs/Cluster-VictoriaMetrics.md index 55eac8188..38241f645 100644 --- a/docs/Cluster-VictoriaMetrics.md +++ b/docs/Cluster-VictoriaMetrics.md @@ -306,10 +306,10 @@ Each node type - `vminsert`, `vmselect` and `vmstorage` - can run on the most su The needed storage space for the given retention (the retention is set via `-retentionPeriod` command-line flag at `vmstorage`) can be extrapolated from disk space usage in a test run. For example, if the storage space usage is 10GB after a day-long test run on a production workload, then it will need at least `10GB*100=1TB` of disk space for `-retentionPeriod=100d` (100-days retention period). Storage space usage can be monitored with [the official Grafana dashboard for VictoriaMetrics cluster](#monitoring). -It is recommended leaving the following amounts of spare resources on every node type for reducing the probability of issues related to temporary spikes in the workload: +It is recommended leaving the following amounts of spare resources: -* 50% of free RAM -* 50% of spare CPU +* 50% of free RAM across all the node types for reducing the probability of OOM (out of memory) crashes and slowdowns during temporary spikes in workload. +* 50% of spare CPU across all the node types for reducing the probability of slowdowns during temporary spikes in workload. * At least 30% of free storage space at the directory pointed by `-storageDataPath` command-line flag at `vmstorage` nodes. Some capacity planning tips for VictoriaMetrics cluster: diff --git a/docs/README.md b/docs/README.md index c925904d3..95d2e95bd 100644 --- a/docs/README.md +++ b/docs/README.md @@ -1106,10 +1106,10 @@ VictoriaMetrics capacity scales linearly with the available resources. The neede The needed storage space for the given retention (the retention is set via `-retentionPeriod` command-line flag) can be extrapolated from disk space usage in a test run. For example, if `-storageDataPath` directory size becomes 10GB after a day-long test run on a production workload, then it will need at least `10GB*100=1TB` of disk space for `-retentionPeriod=100d` (100-days retention period). -It is recommended leaving the following amounts of spare resources for reducing the probability of issues related to temporary spikes in the workload: +It is recommended leaving the following amounts of spare resources: -* 50% of free RAM -* 50% of spare CPU +* 50% of free RAM for reducing the probability of OOM (out of memory) crashes and slowdowns during temporary spikes in workload. +* 50% of spare CPU for reducing the probability of slowdowns during temporary spikes in workload. * At least 30% of free storage space at the directory pointed by `-storageDataPath` command-line flag. diff --git a/docs/Single-server-VictoriaMetrics.md b/docs/Single-server-VictoriaMetrics.md index 6b1cb6b14..fe9367247 100644 --- a/docs/Single-server-VictoriaMetrics.md +++ b/docs/Single-server-VictoriaMetrics.md @@ -1110,10 +1110,10 @@ VictoriaMetrics capacity scales linearly with the available resources. The neede The needed storage space for the given retention (the retention is set via `-retentionPeriod` command-line flag) can be extrapolated from disk space usage in a test run. For example, if `-storageDataPath` directory size becomes 10GB after a day-long test run on a production workload, then it will need at least `10GB*100=1TB` of disk space for `-retentionPeriod=100d` (100-days retention period). -It is recommended leaving the following amounts of spare resources for reducing the probability of issues related to temporary spikes in the workload: +It is recommended leaving the following amounts of spare resources: -* 50% of free RAM -* 50% of spare CPU +* 50% of free RAM for reducing the probability of OOM (out of memory) crashes and slowdowns during temporary spikes in workload. +* 50% of spare CPU for reducing the probability of slowdowns during temporary spikes in workload. * At least 30% of free storage space at the directory pointed by `-storageDataPath` command-line flag.