https://jira.whamcloud.com This file is an XML representation of an issue en-us 9.4.14 940014 05-12-2023 https://jira.whamcloud.com/browse/LU-13591 Lustre <p>Using 'lazytime' when mounting MGS/MDS/OSS seems to offer performance advantages for 4.x and later kernels (where ldiskfs has support for lazytime).</p> <p>Enable this feature by default.</p> LU-13591

Enable lazytime mount for service nodes

Improvement Minor Closed Cannot Reproduce Shaun Tancheff Shaun Tancheff Thu, 21 May 2020 14:34:58 +0000 Sun, 24 May 2020 06:23:42 +0000 Fri, 22 May 2020 14:22:22 +0000 0 2 <p>Do you have any numbers to back this assertion? Since Lustre doesn't actually use/want the kernel updating the timestamps in the files, I don't think "lazytime" would make any difference there.</p> <p>It might make sense to add a "lazytime" mount option to the client, to minimize atime updates, if the clients don't already have "noatime" as a mount option. The MDS will already squash atime updates less than <tt>mdt.&#42;.atime_diff</tt> seconds (default 60s) apart, but if the clients only send an atime update at most once a day that would be even better.</p> <p>The early testing that showed some improvement did not show any advantage on subsequent runs.<br/> It seems this ticket was opened too optimistically.</p> <p>Further benchmarking shows no clear advantage to lazytime on service nodes.</p> <p>I wouldn't be against implementing lazytime for the client, but that is up to you.</p> Development Rank 1|i010xr: Rank (Obsolete) 9223372036854775807