Hello everybody,
I'm facing the somewhat difficult task of looking under the hood of the
knfsd and profiling its behaviour on WRITE/COMMIT calls. Basically, I'd
like to answer the following questions:
- What amount of payload is comming in?
- What WRITE flags are set (UNSTABLE/DATA_SYNC/FILE_SYNC)?
- What happens to the incoming RPCs (are they stored in a queue, or cached
if UNSTABLE is set? If yes, what is the queue/cache size)?
- What does the nfsd write out to disk?
- How many NFS I/O operations are a kernel VFS (?) operation, and how many
FS IOPs does this make?
Regarding the last question, I already have a way of finding out what I/O
operations containing what payload are done with what delay.
I'm a little at loss here because I have only a very vague idea of where to
look. I though using systemtap and tapping some functions would give me
answers to the questions above. Could somebody give me please some
pointers, be it function names, header files, or a general idea of the call
flow a NFS WRITE packet creates from being received over a socket until it
is written out to disk?
Thank you very much in advance.
Eric
--
Eric MSP Veith <eric.veith@xxxxxxxxxx>
Hechtsheimer Str. 2
DE-55131 Mainz
Germany
IBM Deutschland GmbH
Vorsitzender des Aufsichtsrats: Erich Clementi
Geschäftsführung: Martin Jetter (Vorsitzender), Reinhard Reschke, Christoph
Grandpierre, Matthias Hartmann, Michael Diemer, Martina Koederitz
Sitz der Gesellschaft: Stuttgart
Registergericht: Amtsgericht Stuttgart, HRB 14562
WEEE-Reg.-Nr. DE 99369940
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
