[Gluster-devel] Major slowdown in cp performance in 1.4 branch

Tue Aug 26 18:28:46 UTC 2008

Without the AFRs in the setup, writes are very fast.  56-58MBps for dd, 6 
minutes for my "cp -a" (normally takes ~9 minutes with AFRs in place, 
currently takes > 1hr with AFRs).

It appears that a recent AFR change (perhaps over the weekend?) is killing 
write performance.

Thanks,

Brent

On Tue, 26 Aug 2008, Brent A Nelson wrote:

> No, I noticed the trace translator and removed it yesterday, just before Amar 
> warned me that it was there; no effect.  The crash is gone now, but the 
> slowdown on writes is still an issue.  Avati's suggestion sounds good; I'll 
> try keeping my setup intact, but eliminate the AFRs and see what happens.
>
> Thanks,
>
> Brent
>
> On Tue, 26 Aug 2008, Anand Babu Periasamy wrote:
>
>> Avati, trace translator is loaded in this setup. It could have the slowdown 
>> or crash!
>> --
>> Anand Babu Periasamy
>> GPG Key ID: 0x62E15A31
>> Blog [http://ab.freeshell.org]
>> The GNU Operating System [http://www.gnu.org]
>> Z RESEARCH Inc [http://www.zresearch.com]
>> 
>> 
>> 
>> Anand Avati wrote:
>>> Brent,
>>>  do you have a non-AFR volume to compare the write speeds against?
>>> 
>>> avati
>>> 
>>> 2008/8/26 Brent A Nelson <brent at phys.ufl.edu>
>>> 
>>>> I don't seem to be getting this crashing namespace issue anymore with a 
>>>> tla
>>>> from today and adding posix-locks to my namespace exports (which are 
>>>> AFRed,
>>>> and AFR now needs locking, which sounds like a good thing).
>>>> 
>>>> Writes are still just as slow (3.3MBps), but dd reads are very fast
>>>> (~117-118MBps, apparently saturating my gigabit link).
>>>> 
>>>> 
>>>> Thanks,
>>>> 
>>>> Brent
>>>> 
>>>> On Mon, 25 Aug 2008, Brent A Nelson wrote:
>>>>
>>>>  I went to try to test the read performance of that file and got:
>>>>> dd if=/beast/blah0 of=/dev/null bs=1M
>>>>> dd: opening `/beast/blah0': Input/output error
>>>>> ls -al /beast
>>>>> ls: cannot access /beast: No such file or directory
>>>>> df
>>>>> ...
>>>>> glusterfs            5697753088   4054016 5406548992   1% /beast
>>>>> df /beast
>>>>> df: `/beast': No such file or directory
>>>>> df: no file systems processed
>>>>> 
>>>>> Looking through the processes, I see the namespace volumes both died.
>>>>> 
>>>>> Here's the tail end of one log:
>>>>> 
>>>>> 2008-08-25 17:57:43 N [trace.c:1117:trace_lookup] ns0: callid: 420040
>>>>> (*this=0x8052ff8, loc=0xbf99a9a0 {path=/blah0, inode=0x80a2070} )
>>>>> 2008-08-25 17:57:43 N [trace.c:535:trace_lookup_cbk] ns0: callid: 420040
>>>>> (*this=0x8052ff8, op_ret=0, op_errno=61, inode=0x80a2070, 
>>>>> *buf=0xbf99a864
>>>>> {st_dev=65031, st_ino=28855, st_mode=33188, st_nlink=1, st_uid=0, 
>>>>> st_gid=0,
>>>>> st_rdev=0, st_size=0, st_blksize=4096, st_blocks=0})
>>>>> 2008-08-25 17:57:43 N [trace.c:1505:trace_open] ns0: (*this=0x8052ff8,
>>>>> loc=0x80adf20 {path=/blah0, inode=0x80a2070}, flags=32768, fd=0x80988e8)
>>>>> 2008-08-25 17:57:43 N [trace.c:150:trace_open_cbk] ns0: 
>>>>> (*this=0x8052ff8,
>>>>> op_ret=0, op_errno=0, *fd=0x80988e8)
>>>>> 2008-08-25 17:57:43 W [common-utils.c:156:gf_print_bytes] glusterfs: 
>>>>> Total
>>>>> data (in bytes): transfered (47460701), received (41736499)
>>>>> pending frames:
>>>>> frame : type(1) op(40)
>>>>> 
>>>>> Signal received: 11/lib/tls/i686/cmov/libc.so.6[0xb7d99128]
>>>>> /usr/lib/libglusterfs.so.0(default_gf_lk+0xb4)[0xb7ee8724]
>>>>> 
>>>>> /usr/lib/glusterfs/1.4.0qa34/xlator/protocol/server.so(server_lk_common+0x6ff)[0xb7cf93df]
>>>>> 
>>>>> /usr/lib/glusterfs/1.4.0qa34/xlator/protocol/server.so(server_gf_lk+0x48)[0xb7cf95d8]
>>>>> 
>>>>> /usr/lib/glusterfs/1.4.0qa34/xlator/protocol/server.so(protocol_server_interpret+0xd6)[0xb7cf41e6]
>>>>> 
>>>>> /usr/lib/glusterfs/1.4.0qa34/xlator/protocol/server.so(protocol_server_pollin+0xb3)[0xb7cf43e3]
>>>>> 
>>>>> /usr/lib/glusterfs/1.4.0qa34/xlator/protocol/server.so(notify+0x51)[0xb7cf44e1]
>>>>> /usr/lib/glusterfs/1.4.0qa34/transport/socket.so[0xb74e7f3a]
>>>>> /usr/lib/libglusterfs.so.0[0xb7ef6a45]
>>>>> /usr/lib/libglusterfs.so.0(event_dispatch+0x21)[0xb7ef5661]
>>>>> glusterfsd(main+0x953)[0x804a163]
>>>>> /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe0)[0xb7d84450]
>>>>> glusterfsd[0x80497a1]
>>>>> ---------
>>>>> 
>>>>> 
>>>>> Thanks,
>>>>> 
>>>>> Brent
>>>>> 
>>>>> On Mon, 25 Aug 2008, Brent A Nelson wrote:
>>>>>
>>>>>  3.2 MBps, which is far less than previous, on a "dd if=/dev/zero
>>>>>> of=/beast/blah0 bs=1M count=10000"
>>>>>> 
>>>>>> Thanks,
>>>>>> 
>>>>>> Brent
>>>>>> 
>>>>>> On Mon, 25 Aug 2008, Amar S. Tumballi wrote:
>>>>>>
>>>>>>  Brent,
>>>>>>> Can you check the dd speed too? One user on irc reported very slow cp
>>>>>>> performance too, but his dd performance was good.
>>>>>>> 
>>>>>>> Regards,
>>>>>>> 
>>>>>>> 2008/8/25 Brent A Nelson <brent at phys.ufl.edu>
>>>>>>>
>>>>>>>  A checkout today from the 1.4 branch seems to give terrible 
>>>>>>> performance
>>>>>>>> on
>>>>>>>> "cp -a".  Something that took a little over 9 minutes from a checkout
>>>>>>>> last
>>>>>>>> week now takes over an hour (it hasn't finished yet).  CPU time
>>>>>>>> consumed by
>>>>>>>> glusterfs and all the glusterfsd processes is quite a bit smaller 
>>>>>>>> than
>>>>>>>> it
>>>>>>>> used to be; it looks like a recent patch is causing a substantial
>>>>>>>> performance issue...
>>>>>>>> 
>>>>>>>> Thanks,
>>>>>>>> 
>>>>>>>> Brent
>>>>>>>> 
>>>>>>>> 
>>>>>>>> _______________________________________________
>>>>>>>> Gluster-devel mailing list
>>>>>>>> Gluster-devel at nongnu.org
>>>>>>>> http://lists.nongnu.org/mailman/listinfo/gluster-devel
>>>>>>>> 
>>>>>>>> 
>>>>>>> 
>>>>>>> --
>>>>>>> Amar Tumballi
>>>>>>> Gluster/GlusterFS Hacker
>>>>>>> [bulde on #gluster/irc.gnu.org]
>>>>>>> http://www.zresearch.com - Commoditizing Super Storage!
>>>>>>> 
>>>>>>> 
>>>> _______________________________________________
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>>>> 
>>> 
>>> 
>>> 
>> 
>