<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<br>
Hi Raghavendra,<br>
<br>
Thanks for the suggestions. Our technician will be in on Monday.
We'll test then and let you know the results.<br>
<br>
One question I have, is the "group metadata-cache" option supposed
to directly impact the performance or is it to help collect data?
If the latter, where will the data be located?<br>
<br>
Thanks again.<br>
<br>
Pat<br>
<br>
<br>
<div class="moz-cite-prefix">On 06/21/2018 01:01 AM, Raghavendra
Gowdappa wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAFkORY9Bh-HpHF0t=ThVGyVb5zfocOp2xkgC7-HgZo8Wfr1j4A@mail.gmail.com">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Thu, Jun 21, 2018 at 10:24 AM,
Raghavendra Gowdappa <span dir="ltr"><<a
href="mailto:rgowdapp@redhat.com" target="_blank"
moz-do-not-send="true">rgowdapp@redhat.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>
<div>
<div>
<div>
<div>
<div>
<div>For the case of writes to glusterfs
mount,<br>
<br>
</div>
I saw in earlier conversations that there
are too many lookups, but small number of
writes. Since writes cached in write-behind
would invalidate metadata cache, lookups
won't be absorbed by md-cache. I am
wondering what would results look like if we
turn off performance.write-behind.<br>
<br>
</div>
@Pat,<br>
<br>
</div>
Can you set,<br>
<br>
</div>
# gluster volume set <volname>
performance.write-behind off<br>
</div>
</div>
</div>
</div>
</blockquote>
<div><br>
</div>
<div>Please turn on "group metadata-cache" for write tests
too.</div>
<div> <br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>
<div>
<div><br>
</div>
and redo the tests writing to glusterfs mount? Let
us know about the results you see.<br>
<br>
</div>
regards,<br>
</div>
Raghavendra<br>
</div>
<div class="HOEnZb">
<div class="h5">
<div class="gmail_extra"><br>
<div class="gmail_quote">On Thu, Jun 21, 2018 at
8:33 AM, Raghavendra Gowdappa <span dir="ltr"><<a
href="mailto:rgowdapp@redhat.com"
target="_blank" moz-do-not-send="true">rgowdapp@redhat.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0
0 .8ex;border-left:1px #ccc
solid;padding-left:1ex">
<div dir="ltr"><br>
<div class="gmail_extra"><br>
<div class="gmail_quote"><span>On Thu, Jun
21, 2018 at 8:32 AM, Raghavendra
Gowdappa <span dir="ltr"><<a
href="mailto:rgowdapp@redhat.com"
target="_blank"
moz-do-not-send="true">rgowdapp@redhat.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div dir="ltr">
<div>
<div>For the case of reading from
Glusterfs mount, read-ahead
should help. However, we've
known issues with
read-ahead[1][2]. To work around
these, can you try with,<br>
<br>
</div>
1. Turn off
performance.open-behind<br>
</div>
#gluster volume set <volname>
performance.open-behind off<br>
<br>
<div>2. enable group meta
metadata-cache<br>
# gluster volume set
<volname> group
metadata-cache</div>
</div>
</blockquote>
<div><br>
</div>
</span>
<div>[1] <a
href="https://bugzilla.redhat.com/show_bug.cgi?id=1084508"
target="_blank" moz-do-not-send="true">https://bugzilla.redhat.com/sh<wbr>ow_bug.cgi?id=1084508</a></div>
<div>[2] <a
href="https://bugzilla.redhat.com/show_bug.cgi?id=1214489"
target="_blank" moz-do-not-send="true">https://bugzilla.redhat.com/sh<wbr>ow_bug.cgi?id=1214489</a></div>
<span>
<div><br>
</div>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div dir="ltr">
<div>
<div>
<div
class="m_-7085830777103976589m_-1104802400275053683gmail-m_5499637752699686457h5"><br>
<br>
<div>
<div>
<div>
<div class="gmail_extra"><br>
<div
class="gmail_quote">On
Thu, Jun 21, 2018 at
5:00 AM, Pat Haley <span
dir="ltr"><<a
href="mailto:phaley@mit.edu"
target="_blank"
moz-do-not-send="true">phaley@mit.edu</a>></span> wrote:<br>
<blockquote
class="gmail_quote"
style="margin:0px
0px 0px
0.8ex;border-left:1px
solid
rgb(204,204,204);padding-left:1ex"><br>
Hi,<br>
<br>
We were recently
revisiting our
problems with the
slowness of
gluster writes (<a
href="http://lists.gluster.org/pipermail/gluster-users/2017-April/030529.html"
rel="noreferrer"
target="_blank"
moz-do-not-send="true">http://lists.gluster.org/pipe<wbr>rmail/gluster-users/2017-April<wbr>/030529.html</a>).
Specifically we
were testing the
suggestions in a
recent post (<a
href="http://lists.gluster.org/pipermail/gluster-users/2018-March/033699.html"
rel="noreferrer"
target="_blank"
moz-do-not-send="true">http://lists.gluster.org/pipe<wbr>rmail/gluster-users/2018-March<wbr>/033699.html</a>).
The first two
suggestions
(specifying a
negative-timeout
in the mount
settings or adding
rpc-auth-allow-insecure to glusterd.vol) did not improve our
performance, while
setting
"disperse.eager-lock
off" provided a
tiny (5%)
speed-up.<br>
<br>
Some of the
various tests we
have tried earlier
can be seen in the
links below. Do
any of the above
observations
suggest what we
could try next to
either improve the
speed or debug the
issue? Thanks<br>
<br>
<a
href="http://lists.gluster.org/pipermail/gluster-users/2017-June/031565.html"
rel="noreferrer"
target="_blank"
moz-do-not-send="true">http://lists.gluster.org/piper<wbr>mail/gluster-users/2017-June/0<wbr>31565.html</a><br>
<a
href="http://lists.gluster.org/pipermail/gluster-users/2017-May/030937.html"
rel="noreferrer"
target="_blank"
moz-do-not-send="true">http://lists.gluster.org/piper<wbr>mail/gluster-users/2017-May/03<wbr>0937.html</a><br>
<br>
Pat<br>
<br>
-- <br>
<br>
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=<wbr>-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=<wbr>-=-=-<br>
Pat Haley
Email: <a
href="mailto:phaley@mit.edu"
target="_blank"
moz-do-not-send="true">phaley@mit.edu</a><br>
Center for Ocean
Engineering
Phone: (617)
253-6824<br>
Dept. of
Mechanical
Engineering
Fax: (617)
253-8125<br>
MIT, Room 5-213
<a
href="http://web.mit.edu/phaley/www/" rel="noreferrer" target="_blank"
moz-do-not-send="true">http://web.mit.edu/phaley/www/</a><br>
77 Massachusetts
Avenue<br>
Cambridge, MA
02139-4301<br>
<br>
______________________________<wbr>_________________<br>
Gluster-users
mailing list<br>
<a
href="mailto:Gluster-users@gluster.org"
target="_blank"
moz-do-not-send="true">Gluster-users@gluster.org</a><br>
<a
href="http://lists.gluster.org/mailman/listinfo/gluster-users"
rel="noreferrer"
target="_blank"
moz-do-not-send="true">http://lists.gluster.org/mailm<wbr>an/listinfo/gluster-users</a></blockquote>
</div>
<br>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
</span></div>
<br>
</div>
</div>
</blockquote>
</div>
<br>
</div>
</div>
</div>
</blockquote>
</div>
<br>
</div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Pat Haley Email: <a class="moz-txt-link-abbreviated" href="mailto:phaley@mit.edu">phaley@mit.edu</a>
Center for Ocean Engineering Phone: (617) 253-6824
Dept. of Mechanical Engineering Fax: (617) 253-8125
MIT, Room 5-213 <a class="moz-txt-link-freetext" href="http://web.mit.edu/phaley/www/">http://web.mit.edu/phaley/www/</a>
77 Massachusetts Avenue
Cambridge, MA 02139-4301
</pre>
</body>
</html>