Re: Why is the performance of my lvmthin snapshot so poor
Gionatan Danti <[email protected]>
| Newsgroups | gmane.linux.lvm.general |
|---|---|
| Message-ID | <[email protected]> |
Il 2022-06-14 12:16 Zhiyong Ye ha scritto: > After creating the PV and VG based on the iSCSI device, I created the > thin pool as follows: > lvcreate -n pool -L 1000G test-vg > lvcreate -n poolmeta -L 100G test-vg > lvconvert --type thin-pool --chunksize 64k --poolmetadata > test-vg/poolmeta test-vg/pool > lvchange -Z n test-vg/pool I did my performance test with bigger chunk size, in the range of 128-512K. It can very well be that the overload of a smaller chunk size results in 10x lower IOPs for to-be-allocated-and-copied chunks. Can you retry fio after increasing chunk size? As a side not, if I remember correcly thin pool metadata is hard limited do 16 GB - no need to allocate 100 GB for it. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: [email protected] - [email protected] GPG public key ID: FF5F32A8 _______________________________________________ linux-lvm mailing list [email protected] https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/