Are these single threaded writes that you are referring to? It certainly appears so from the thread, but I thought it would be good to confirm that before digging in further.
David Byte
Sr. Technology Strategist
SCE Enterprise Linux
SCE Enterprise Storage
Alliances and SUSE Embedded
dbyte@xxxxxxxx
918.528.4422
From: ceph-users <ceph-users-bounces@xxxxxxxxxxxxxx> on behalf of Joe Comeau <Joe.Comeau@xxxxxxxxxx>
Date: Friday, August 31, 2018 at 1:07 PM
To: "ceph-users@xxxxxxxxxxxxxx" <ceph-users@xxxxxxxxxxxxxx>, Peter Eisch <Peter.Eisch@xxxxxxxxxxxxxxx>
Subject: Re: [ceph-users] cephfs speed
Are you using bluestore OSDs ?
if so my thought process on this is what we are having an issue with is caching and bluestore
see the thread on bluestore caching
"Re: [ceph-users] Best practices for allocating memory to bluestore cache"
before when we were on Jewel and filestore we could get a much better sustained write
Now on bluestore we are not getting more than a sustained 2GB file write before it drastically slows down
Then it fluctuates from 0kb/s to 100MB/s and back and forth as it is writing
>>> Peter Eisch <Peter.Eisch@xxxxxxxxxxxxxxx> 8/31/2018 10:31 AM >>>
[replying to myself]
I set aside cephfs and created an rbd volume. I get the same splotchy throughput with rbd as I was getting with cephfs. (image attached)
So, withdrawing this as a question here as a cephfs issue.
#backingout
peter
|
|
|
|
|
|
|
Australia | Bosnia and Herzegovina | Brazil | Canada | Singapore | Switzerland | United Kingdom | USA
|
|
|
Confidentiality Notice: The information contained in this e-mail, including any attachment(s), is intended solely for use by the designated recipient(s). Unauthorized use, dissemination,
distribution, or reproduction of this message by anyone other than the intended recipient(s), or a person designated as responsible for delivering such messages to the intended recipient, is strictly prohibited and may be unlawful. This e-mail may contain
proprietary, confidential or privileged information. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Virgin Pulse, Inc. If you have received this message in error, or are not the named recipient(s),
please immediately notify the sender and delete this e-mail message.
|
|
|
|
|
On 8/30/18, 12:25 PM, "Peter Eisch" <Peter.Eisch@xxxxxxxxxxxxxxx> wrote:
Thanks for the thought. It’s mounted with this entry in fstab (one line, if email wraps it):
cephmon-s01,cephmon-s02,cephmon-s03:/ /loam ceph noauto,name=clientname,secretfile=/etc/ceph/secret,noatime,_netdev 0 2
Pretty plain, but I'm open to tweaking!
peter
From: Gregory Farnum <gfarnum@xxxxxxxxxx>
Date: Thursday, August 30, 2018 at 11:47 AM
To: Peter Eisch <Peter.Eisch@xxxxxxxxxxxxxxx>
Cc: "ceph-users@xxxxxxxxxxxxxx" <ceph-users@xxxxxxxxxxxxxx>
Subject: Re: [ceph-users] cephfs speed
How are you mounting CephFS? It may be that the cache settings are just set very badly for a 10G pipe. Plus rados bench is a very parallel large-IO benchmark and many benchmarks you might dump into a filesystem are definitely not.
-Greg
On Thu, Aug 30, 2018 at 7:54 AM Peter Eisch <mailto:Peter.Eisch@xxxxxxxxxxxxxxx> wrote:
Hi,
I have a cluster serving cephfs and it works. It’s just slow. Client is using the kernel driver. I can ‘rados bench’ writes to the cephfs_data pool at wire speeds (9580Mb/s on a 10G link) but when I copy data into cephfs it is rare to get above 100Mb/s. Large
file writes may start fast (2Gb/s) but within a minute slows. In the dashboard at the OSDs I get lots of triangles (it doesn't stream) which seems to be lots of starts and stops. By contrast the graphs show constant flow when using 'rados bench.'
I feel like I'm missing something obvious. What can I do to help diagnose this better or resolve the issue?
Errata:
Version: 12.2.7 (on everything)
mon: 3 daemons, quorum cephmon-s01,cephmon-s03,cephmon-s02
mgr: cephmon-s02(active), standbys: cephmon-s01, cephmon-s03
mds: cephfs1-1/1/1 up {0=cephmon-s02=up:active}, 2 up:standby
osd: 70 osds: 70 up, 70 in
rgw: 3 daemons active
rados bench summary:
Total time run: 600.043733
Total writes made: 167725
Write size: 4194304
Object size: 4194304
Bandwidth (MB/sec): 1118.09
Stddev Bandwidth: 7.23868
Max bandwidth (MB/sec): 1140
Min bandwidth (MB/sec): 1084
Average IOPS: 279
Stddev IOPS: 1
Max IOPS: 285
Min IOPS: 271
Average Latency(s): 0.057239
Stddev Latency(s): 0.0354817
Max latency(s): 0.367037
Min latency(s): 0.0120791
peter
Peter Eisch
https://www.virginpulse.com/
|
https://globalchallenge.virginpulse.com/
Australia | Bosnia and Herzegovina | Brazil | Canada | Singapore | Switzerland | United Kingdom | USA
Confidentiality Notice: The information contained in this e-mail, including any attachment(s), is intended solely for use by the designated recipient(s). Unauthorized use, dissemination, distribution, or reproduction of this message by anyone other than the
intended recipient(s), or a person designated as responsible for delivering such messages to the intended recipient, is strictly prohibited and may be unlawful. This e-mail may contain proprietary, confidential or privileged information. Any views or opinions
expressed are solely those of the author and do not necessarily represent those of Virgin Pulse, Inc. If you have received this message in error, or are not the named recipient(s), please immediately notify the sender and delete this e-mail message.
v2.10
_______________________________________________
ceph-users mailing list
mailto:ceph-users@xxxxxxxxxxxxxx
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
|
