Have you modified/sys/block/sdk/queue/read_ahead_kb read_ahead?
Modified to 8192, the default value is 128;
is the SATA disk OSD changed to 8192? How much of a performance boost?
In addition, this value should be modified at any time, right? Can it be dynamically adjusted after deployment?
What effect will it have on the OSD?
can improve read performance
Can be modified in real time
What does this parameter mean?
Pre-read bytes?
This parameter is useful for sequential reads, meaning how much content to read in advance, regardless of the actual need. The default time to read 128kb is much smaller than to read, set larger to read large files is very useful, can effectively reduce the number of read seek, this parameter can be set by using Blockdev–setra, Setra set how many sectors, so the actual byte is divided by 2, such as set 512, is actually read 256 bytes.
The OSD disk changed this parameter will also affect it?
The default object is 4096, so you want to set 8192?
Ceph for finishing
