HI Ben, yes we have the same issues and switched to seagate for those reasons.
you can fix at least a big part of it by disabling the write cache of those drives - generally speaking it seems the toshiba firmware is broken. I was not able to find a newer one. Greets, Stefan Am 24.06.20 um 09:43 schrieb Benoît Knecht: > Hi, > > We have a Nautilus (14.2.9) Ceph cluster with two types of HDDs: > > - TOSHIBA MG07ACA14TE [1] > - HGST HUH721212ALE604 [2] > > They're all bluestore OSDs with no separate DB+WAL and part of the same pool. > > We noticed that while the HGST OSDs have a commit latency of about 15ms, the > Toshiba OSDs hover around 150ms (these values come from the > `ceph_osd_commit_latency_ms` metric in Prometheus). > > On paper, it seems like those drives have very similar specs, so it's not > clear to me why we're seeing such a large difference when it comes to commit > latency. > > Has anyone had any experience with those Toshiba drives? Or looking at the > specs, do you spot anything suspicious? > > And if you're running a Ceph cluster with various disk brands/models, have > you ever noticed some of them standing out when looking at > `ceph_osd_commit_latency_ms`? > > Thanks in advance for your feedback. > > Cheers, > > -- > Ben > > [1]: > https://toshiba.semicon-storage.com/content/dam/toshiba-ss/asia-pacific/docs/product/storage/product-manual/eHDD-MG07ACA-Product-Manual.pdf > [2]: > https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/data-center-drives/ultrastar-dc-hc500-series/data-sheet-ultrastar-dc-hc520.pdf > _______________________________________________ > ceph-users mailing list -- ceph-users@ceph.io > To unsubscribe send an email to ceph-users-le...@ceph.io > _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-le...@ceph.io
