From a645450f1e247f059881d05220eee702fd9b3664 Mon Sep 17 00:00:00 2001 From: Ziv Caspi Date: Mon, 16 Feb 2026 20:42:01 +0200 Subject: [PATCH 1/2] .show extents: Added perf recommendations --- .../kusto/management/show-extents.md | 22 ++++++++++++++----- 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/data-explorer/kusto/management/show-extents.md b/data-explorer/kusto/management/show-extents.md index 39c5f569c7..ac444b98e7 100644 --- a/data-explorer/kusto/management/show-extents.md +++ b/data-explorer/kusto/management/show-extents.md @@ -22,12 +22,22 @@ The types of `.show extents` commands are as follows: * Show some or all extents for the entire [cluster](#cluster-scope) > [!NOTE] -> The `.show extents` command may consume a lot of resources if it runs on a scope -> (such as a database or a cluster) with many extents. We recommended -> using the command variant at the lowest possible scope. Table-scope -> is preferable over database-scope, and database-scope over cluster-scope. The -> command variant that includes filtering extents is preferable to filtering the results -> of the command using another query. +> The `.show extents` command may consume a lot of resources, and even +> exceed internal limits if run at a scope (such as a database or a cluster) +> that has many extents (more than 5 millions.) +> +> For purposes of monitoring the number of extents, it's **strongly recommended** +> that alternative methods (such as using [.show databases datastats](./show-databases.md), +> [.show database datastats](./show-database.md), or [.show tables details](./show-tables.md), +> and [.show table details](./show-table-details-command.md)) be used. Another efficient way +> to retrieve the number of extents is to use a metric exposed through [Azure Monitor](../../monitor-data-explorer-reference.md) +> ("Total Extents"). +> +> If detailed listing of extents is required, be sure to use the "smallest" +> appropriate command scope (table) over the "larger" ones (database, cluster). +> +> Also, prefer using the command variant that includes extent filtering capabilities as part of the +> command's syntax to using the command and processing its results by "piping" them to a query. ## Permissions From 90bc1b73f36c340354d769bdd316bbc3501bd4a3 Mon Sep 17 00:00:00 2001 From: Ziv Caspi Date: Mon, 16 Feb 2026 21:02:27 +0200 Subject: [PATCH 2/2] Warning fixes --- data-explorer/kusto/management/show-extents.md | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/data-explorer/kusto/management/show-extents.md b/data-explorer/kusto/management/show-extents.md index ac444b98e7..54b9f0ca2c 100644 --- a/data-explorer/kusto/management/show-extents.md +++ b/data-explorer/kusto/management/show-extents.md @@ -28,10 +28,9 @@ The types of `.show extents` commands are as follows: > > For purposes of monitoring the number of extents, it's **strongly recommended** > that alternative methods (such as using [.show databases datastats](./show-databases.md), -> [.show database datastats](./show-database.md), or [.show tables details](./show-tables.md), +> [.show database datastats](./show-database.md), or [.show tables details](./show-tables-command.md), > and [.show table details](./show-table-details-command.md)) be used. Another efficient way -> to retrieve the number of extents is to use a metric exposed through [Azure Monitor](../../monitor-data-explorer-reference.md) -> ("Total Extents"). +> to retrieve the number of extents is to use a metric exposed through Azure Monitor ("Total Extents"). > > If detailed listing of extents is required, be sure to use the "smallest" > appropriate command scope (table) over the "larger" ones (database, cluster).