On Sat, Aug 18, 2012 at 10:49:31AM +0400, Michael Tokarev wrote: > On 18.08.2012 02:32, J. Bruce Fields wrote: > > On Fri, Aug 17, 2012 at 04:08:07PM -0400, J. Bruce Fields wrote: > >> Wait a minute, that assumption's a problem because that calculation > >> depends in part on xpt_reserved, which is changed here.... > >> > >> In particular, svc_xprt_release() calls svc_reserve(rqstp, 0), which > >> subtracts rqstp->rq_reserved and then calls svc_xprt_enqueue, now with a > >> lower xpt_reserved value. That could well explain this. > > > > So, maybe something like this? > > Well. What can I say? With the change below applied (to 3.2 kernel > at least), I don't see any stalls or high CPU usage on the server > anymore. It survived several multi-gigabyte transfers, for several > hours, without any problem. So it is a good step forward ;) > > But the whole thing seems to be quite a bit fragile. I tried to follow > the logic in there, and the thing is quite a bit, well, "twisted", and > somewhat difficult to follow. So I don't know if this is the right > fix or not. At least it works! :) Suggestions welcomed. > And I really wonder why no one else reported this problem before. > Is me the only one in this world who uses linux nfsd? :) This, for example: http://marc.info/?l=linux-nfs&m=134131915612287&w=2 may well describe the same problem.... It just needed some debugging persistence, thanks! --b. -- 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
