Hi, I recently upgraded my 3-node cluster to proxmox 6 / debian-10 and recreated my ceph cluster with a new release (14.2.4 bluestore) - basically hoping to gain some I/O speed. The installation went flawlessly, reading is faster than before (~ 80 MB/s), however, the write speed is still really slow (~ 3,5 MB/s). I wonder if I can do anything to speed things up? My Hardware is as the following: 3 Nodes with Supermicro X8DTT-HIBQF Mainboard each, 2 OSD per node (2TB SATA harddisks, WDC WD2000F9YZ-0), interconnected via Infiniband 40 The network should be reasonably fast, I measure ~ 16 GBit/s with iperf, so this seems fine. I use ceph for RBD only, so my measurement is simply doing a very simple "dd" read and write test within a virtual machine (Debian 8) like the following: read: dd if=/dev/vdb | pv | dd of=/dev/null -> 80 MB/s write: dd if=/dev/zero | pv | dd of=/dev/vdb -> 3.5 MB/s When I do the same on the virtual machine on a disk that is on a NFS storage, I get something about 30 MB/s for reading and writing. If I disable the write cache on all OSD disks via "hdparm -W 0 /dev/sdX", I gain a little bit of performance, write speed is then 4.3 MB/s. Thanks to your help from the list I plan to install a second ceph cluster which is SSD based (Samsung PM1725b) which should be much faster, however, I still wonder if there is any way to speed up my harddisk based cluster? Thank you in advance for any help, Best Regards, Hermann -- hermann@xxxxxxx PGP/GPG: 299893C7 (on keyservers) _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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