> -----Original Message----- > From: linux-nfs-owner@xxxxxxxxxxxxxxx [mailto:linux-nfs-owner@xxxxxxxxxxxxxxx] > On Behalf Of Jim Rees > Sent: Wednesday, September 21, 2011 8:29 AM > To: Trond Myklebust > Cc: Benny Halevy; linux-nfs@xxxxxxxxxxxxxxx; peter honeyman > Subject: Re: [PATCH 2/3] pnfs: introduce pnfs private workqueue > > Trond Myklebust wrote: > > On Mon, 2011-09-19 at 23:18 -0400, Jim Rees wrote: > > From: Peng Tao <bergwolf@xxxxxxxxx> > > > > For layoutdriver io done functions, default workqueue is not a good place as > > the code is executed in IO path. So add a pnfs private workqueue to handle > > them. > > > > Also change block and object layout code to make use of this private > > workqueue. > > > > Wait, what???? > > Why is the I/O path (i.e. the nfsiod queue) inappropriate for > layoutdriver io_done functions? The current code uses the system_wq to handle io_done functions. If any function allocates memory in system_wq and causes dirty writeback in nfs path, the io_done function can never be called because it is after the original function in the system_wq. And you said that the rpciod/nfsiod is not the ideal place because of memory allocation. So I suggested pnfs private workqueue and Benny agreed on it. > > I thought you were the one who asked for this, here: > http://www.spinics.net/lists/linux-nfs/msg22771.html > > But looking back on it now, the IO path has changed and I can't tell if the > argument still holds. I believe it still holds. The recollapse path still involves memory allocation. Cheers, Tao -- 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
