[Samba] CTDB / Samba / GFS2 - Performance - with Picture Link

[Vogel, Sven]

Hi Volker,

so i looked fort he brlock.tdb file and its local on each node. I added "posix locking = no" and "locking = no". I think it will run now better. I again a strace file to the server. What do you think?

http://dev.kupper-computer.com/intern/smbd_no_locking.txt

I also added 

fileid:algorithm = fsname
vfs objects = fileid

for gfs2 whats better fsid or fileid? 

Thanks 

Sven

-----Ursprüngliche Nachricht-----
Von: Volker Lendecke [mailto:Volker.Lendecke at SerNet.DE] 
Gesendet: Dienstag, 27. November 2012 17:05
An: Vogel, Sven
Cc: samba at lists.samba.org
Betreff: Re: [Samba] CTDB / Samba / GFS2 - Performance - with Picture Link

On Tue, Nov 27, 2012 at 03:50:40PM +0000, Vogel, Sven wrote:
> Hi Volker,
> 
> thanks for the fast reply. So used the strace command. I am not so a 
> strace specialist but is it possible that the problem are the many 
> polls?`
> 
> 12513 15:33:24.593065 poll([{fd=9, events=POLLIN|POLLHUP}, {fd=7, 
> events=POLLIN|POLLHUP}, {fd=40, events=POLLIN|POLLHUP}, {fd=32, 
> events=POLLIN|POLLHUP}, {fd=34, events=POLLIN|POLLHUP}], 5, 4436) = 1 
> ([{fd=32, revents=POLLIN}]) <0.002497>
> 12513 15:33:24.595615 read(32, "\0\0\0T", 4) = 4 <0.000017>
> 
> i added a link to the strace. I dont see which syscalls take long. 
> There are such many syscalls in any second so i dont know whats 
> normal. :-|
> 
> http://dev.kupper-computer.com/intern/smbd.txt
> 
> Did you have any idea?

One question -- do you have your brlock.tdb on gfs? If so, move them to a local file system, they will be taken care of by ctdb. Your fcntl calls on that seem slow. Also, you might want to try "posix locking = no". There is a call at timestamp 15:32:47.383963, 1.9 seconds to find out whether a range is locked. That shows that at this point in time GFS was busy regarding fcntl locks. Also, your network or your client seems to have a problem. For example at timestamp
15:32:51.837717 we are waiting 30 milliseconds for a new request from the client. This is very long for a client continuously trying to write.

Volker

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