Re: SSHFS makes the ROOT launch speed slow?

Hi Akira,

   use Instruments application on MacOS X. It can monitor many things including I/O. Or command line tool dtruss (see man dtruss).

Cheers, Fons.

On 13/02/2011 22:06, OKUMURA, Akira wrote:
> Hello Axel and all,
>
> I am using Mac OS X which does not have strace. Does anyone know a good alternative tool to trace file I/O in root.exe?
>
> Regards,
>
> --
> OKUMURA, Akira oxon@{astro.isas.jaxa.jp,stanford.edu}
> Institute of Space and Astronautical Science (ISAS/JAXA)
> Now at KIPAC/SLAC/Stanford
> Varian Physics #306, 382 Via Pueblo Mall, MC 4060
> Stanford, CA 94305-4060
> TEL 650-736-0971/FAX 650-724-5065
> Skype : okumura.akira
>
> On 2011/02/03, at 5:47, Axel Naumann wrote:
>
>> Hi,
>>
>> run strace on root.exe (yes, on Linux). root invokes root.exe, and I
>> believe that's what you are seeing.
>>
>> Cheers, Axel.
>>
>> Eduard Avetisyan wrote on 02/02/2011 08:55 PM:
>>>
>>>
>>> On Wed, 2 Feb 2011, Konstantin Olchanski wrote:
>>>
>>>> On Wed, Feb 02, 2011 at 08:34:52PM +0100, Eduard Avetisyan wrote:
>>>>>> On Wed, Feb 02, 2011 at 08:04:12PM +0100, Eduard Avetisyan wrote:
>>>>>>>
>>>>>>> The same strace produces ~130 calls in my case, which include but are not
>>>>>>> limited to libraries like:
>>>>>>> open("tls/i686/sse2/libXpm.so.4", O_RDONLY) = -1 ENOENT (No such file or directory)
>>>>>>
>>>>>> You have "." in your LD_LIBRARY_PATH. Remove it and those syscalls will go away.
>>>>>
>>>>> Good hint! Changing the LD_LIBRARY_PATH from ":$ROOTSYS/lib" to simply
>>>>> "$ROOTSYS/lib" (just a colon difference) reduced the startup time from 12s
>>>>> to 8s, so by 1/3. Still, it's way slower than a local startup time of 0.1s.
>>>>>
>>>>
>>>> You are still making the system search for every system library in $ROOTSYS/lib,
>>>> which I understand is a slow SSHFS filesystem.
>>>
>>> Quite the contrary! The $ROOTSYS is local and fast! Only the current
>>> working directory is on SSHFS!
>>>
>>>
>>>>
>>>> You can try to put the system library path (/lib, etc) in front of $ROOTSYS/lib,
>>>> so the loader quickly finds the system libraries and does not touch SSHFS.
>>> Tried, doesn't change anything (as $ROOTSYS is local anyway). But I found
>>> that the slow part happens with the following strace signature:
>>>
>>> clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb73769b8) = 27680
>>> waitpid(27680, root [0] [{WIFEXITED(s)&& WEXITSTATUS(s) == 0}], WSTOPPED) = 27680
>>>
>>> namely, "waitpid(27680," is printed and the rest shows up 8-12 seconds
>>> later.
>>>
>>> Thanks for looking into this!
>>> Eduard
>>>>
>>>> --
>>>> Konstantin Olchanski
>>>> Data Acquisition Systems: The Bytes Must Flow!
>>>> Email: olchansk-at-triumf-dot-ca
>>>> Snail mail: 4004 Wesbrook Mall, TRIUMF, Vancouver, B.C., V6T 2A3, Canada
>>>>
>>>>
>>>
>>
>

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