search for: brendangregg

G''Day Folks, I''ve finally typed up my classic DTrace demo, which I use to introduce people to DTrace (I delivered this at SOSUG#1), http://www.brendangregg.com/DTrace/dtracevstruss.html Here I create a fault and show the difficulty in analysing it using previous tools. Then I compare the impact of analysing the problem using both DTrace and truss. DTrace wins (a lot!). Thanks to the PAE guys from Adelaide for suggesting to run sar -c, it''s...

I am looking for Dtrace scripts that can be used to collect data during performance tests. I am especially interested in IO but CPU, memory, threads, etc are needed as well. Thanks, Dave

...> > . > > Someone have problem with samba4 with centos cpu 100%. ? > > > > Attached my config. > > Where is it spinning? > > With all the required debug packages installed, then run it under > perf > and generate a flame graph per: > > http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html > > The resulting .svg file is often quite enlightening. > > Andrew Bartlett Also, how many users, groups and in particular group members in each group (and in total)? If you have large numbers of group members, then Samba 4.5 will help a lot. Th...

...an see all across the board api refactoring that was done by a bunch of people over the last 5 month didn't cause any problems for them or for the backend - it was accidentally included in the last night builds and reverted today. There were no buildbot issues (afaik) - recent press: http://brendangregg.com/blog/2015-05-15/ebpf-one-small-step.html bpf backend has been in-tree since January and has quite a few users, so I think it's time to graduate it from experimental. Thanks!

G''Day Folks, While I have a few minutes online (which is rare at the moment - travel), let me post about a couple of new scripts. I''ve just uploaded them to http://www.brendangregg.com/dtrace.html. They are to profile user-level functions and libaries; and kernel-level functions and modules. They sample, rather than trace (which can be both good and bad). Here is hotuser sampling functions from a gunzip command, # ./hotuser -c ''gunzip contents.gz'' S...

On 23/09/2019 20:41, Andrew Bartlett wrote: > On Mon, 2019-09-23 at 11:25 +0200, Francesco Malvezzi via samba wrote: >> hi all, >> >> I updated a small domain with 8k object to samba-4.11.0 and the >> database >> conversion from v1 to v2 didn't take a noticeable time. >> >> On the other hand, in a larger domain with 67k object, where the >>

Can someone, more learned in the ways of dtrace point me at what to look at to help understand why the kernel on one machine is using tons of memory, while another machine doing the same task/same user load is not. swapinfo for the "afflicted" machine shows RAM _______Total 16384 Mb RAM Unusable 73 Mb RAM Kernel 9226 Mb RAM Locked 2 Mb RAM Used

...s/LearnAboutSenderIdentification?] >> >> Work out which PIDs are high CPU use: >> >> netstat -avp | grep <PID> >> >> gdb -p <PID> >> bt full >> >> strace -p <PID> >> >> as well as a FlameGraph: >> https://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html#Instructions >> >> I would love to get to the bottom of this. >> Andrew Bartlett which would still be useful. Just a sampling of >> gdb -p <PID> >> bt full would confirm where the server was spending its time. If `bt full` l...

...n you, on the instance with the high-cpu use, at the time it is in that state, run (matching the commands our mailing list user has run): Work out which PIDs are high CPU use: netstat -avp | grep <PID> gdb -p <PID> bt full strace -p <PID> as well as a FlameGraph: https://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html#Instructions I would love to get to the bottom of this. Andrew Bartlett -- Andrew Bartlett (he/him) https://samba.org/~abartlet/ Samba Team Member (since 2001) https://samba.org Samba Team Lead, Catalyst IT https://catalyst.net.nz/services/samba Samb...

I see Intel has released a new tool. Oh, it requires some patches to the kernel to record latency times. Good thing people don''t mind patching their kernels, eh? So who can write the equivalent latencytop.d the fastest? ;-) http://www.latencytop.org/ -- cburgess at qnx.com

...--------------------------------------------------------------------- Tracing... Hit Ctrl-C to end. ------------------------------------------------------------------------ I''ve put up a webrev for this at the following URL: http://cr.opensolaris.org/~cmynhier/brendan/ [1] http://www.brendangregg.com/dtrace.html

...<object>. There's a file view, a function view, a class view, and an inlining view. Each view is sorted by code size, so you can see the largest functions/classes/etc immediately. The *.stats files are just human-readable text files. As it happens, they use the flamegraph format (http://brendangregg.com/flamegraphs.html). This makes it easy to visualize any view as a flamegraph. (If you haven't seen one before, it's a hierarchical visualization where the width of each entry corresponds to its frequency (or in this case size).) To look at code growth between two programs, you'd do:...

...9;s a file view, a function view, a class view, > and an inlining view. Each view is sorted by code size, so you can see the > largest functions/classes/etc immediately. > > The *.stats files are just human-readable text files. As it happens, they use > the flamegraph format (http://brendangregg.com/flamegraphs.html <http://brendangregg.com/flamegraphs.html>). This makes it > easy to visualize any view as a flamegraph. (If you haven't seen one before, > it's a hierarchical visualization where the width of each entry corresponds to > its frequency (or in this case siz...

Is there a trick to listing available providers? I can''t find it.

...unction view, a class view, >> and an inlining view. Each view is sorted by code size, so you can see the >> largest functions/classes/etc immediately. >> >> The *.stats files are just human-readable text files. As it happens, they use >> the flamegraph format (http://brendangregg.com/flamegraphs.html <http://brendangregg.com/flamegraphs.html>). This makes it >> easy to visualize any view as a flamegraph. (If you haven't seen one before, >> it's a hierarchical visualization where the width of each entry corresponds to >> its frequency (or in t...

...t; that state, run (matching the commands our mailing list user has > run): > > Work out which PIDs are high CPU use: > > netstat -avp | grep <PID> > > gdb -p <PID> > bt full > > strace -p <PID> > > as well as a FlameGraph: > https://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html#Instructions > > I would love to get to the bottom of this. > Andrew Bartlett > > > -- > Andrew Bartlett (he/him)?????? https://samba.org/~abartlet/ > Samba Team Member (since 2001) https://samba.org > Samba Team Lead, Catalyst IT??...

...th samba4 with centos cpu 100%. ? > > > > > > Attached my config. > > > > Where is it spinning? > > > > With all the required debug packages installed, then run it under > > perf > > and generate a flame graph per: > > > > http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html > > > > The resulting .svg file is often quite enlightening. > > > > Andrew Bartlett > > Also, how many users, groups and in particular group members in each > group (and in total)? > > If you have large numbers of group mem...

Hello, im authenticating my Owncloud aigainst one of my three domain controller and add a second one of it as failover. The authentication works pretty well. When im trying to share files or folders i have the problem, that it takes a lot of time until i get the username i want to share. Compared to my open ldap the samba4 ad needs about 10-15 seconds more to find a result, thats pretty

...memory > issue. Thanks for confirming that. I think you are probably hitting some pathological behaviours at the TDB layer when handling so many records, perhaps in the free list. The way to debug this, if you are keen to, is to do a debug build of Samba run get a flame graph per: http://www.brendangregg.com/FlameGraphs/cpuflamegraphs.html#Instructions That will get us a better idea of which routines are 'hot' during your in-place upgrade. I do wish you the very best with this and am keen to ensure this works really well for you. Andrew Bartlett -- Andrew Bartlett...

...ect, many run asynchronously to the responsible process. James Dickens has been helping out from an IRC forum - IRC seems like it might be really useful for us to team up in. Well, it especially helps me as I''m thousands of miles away! :) socketsnoop.d is on my website at, http://www.brendangregg.com/DTrace/socketsnoop.d cheers, Brendan _______________________________________________ DTrace mailing list DTrace@opensolaris.org https://www.opensolaris.org/mailman/listinfo/dtrace