thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-21 15:12:02 +00:00
Code Issues Packages Projects Releases Wiki Activity

Update config.xml

Browse Source
This commit is contained in:
alexey-milovidov 2021-02-20 09:49:02 +03:00 committed by GitHub
parent 39f07d62a4
commit 4390cb3d73
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 3 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
programs/server/config.xml
View File

@ -285,10 +285,9 @@
Cache is used when 'use_uncompressed_cache' user setting turned on (off by default).
Uncompressed cache is advantageous only for very short queries and in rare cases.
Note: uncompressed cache is pointless for lz4, because memory bandwidth is slower than multi-core decompression.
Enabling it will only make queries slower.
If number of CPU cores is in order of 100 and memory bandwidth is in range of 100-200 GB/sec,
there is a chance it is also being pointless for zstd.
Note: uncompressed cache can be pointless for lz4, because memory bandwidth
is slower than multi-core decompression on some server configurations.
Enabling it can sometimes paradoxically make queries slower.
-->
<uncompressed_cache_size>8589934592</uncompressed_cache_size>