From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <5408C3C5.6010309@kernel.dk> Date: Thu, 04 Sep 2014 13:55:49 -0600 From: Jens Axboe MIME-Version: 1.0 Subject: Re: [PATCH] fio: fix hangs due to iodepth_low References: <20140904002343.24650.74664.stgit@beardog.cce.hp.com> <5407C19C.1030202@kernel.dk> <5407C227.5060707@kernel.dk> <94D0CD8314A33A4D9D801C0FE68B402958C4DCDC@G4W3202.americas.hpqcorp.net> <5408797F.3070803@kernel.dk> <94D0CD8314A33A4D9D801C0FE68B402958C4F44A@G4W3202.americas.hpqcorp.net> In-Reply-To: <94D0CD8314A33A4D9D801C0FE68B402958C4F44A@G4W3202.americas.hpqcorp.net> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit To: "Elliott, Robert (Server Storage)" , "fio@vger.kernel.org" , "scameron@beardog.cce.hp.com" List-ID: On 09/04/2014 01:42 PM, Elliott, Robert (Server Storage) wrote: > > >> -----Original Message----- >> From: Jens Axboe [mailto:axboe@kernel.dk] >> Sent: Thursday, 04 September, 2014 9:39 AM >> To: Elliott, Robert (Server Storage); fio@vger.kernel.org; >> scameron@beardog.cce.hp.com >> Subject: Re: [PATCH] fio: fix hangs due to iodepth_low >> >> On 09/04/2014 08:27 AM, Elliott, Robert (Server Storage) wrote: >>>>> should be: >>>>> >>>>> if (min_events > td->cur_depth) >>>>> min_events = td->cur_depth; >>>>> >>>>> and we should probably put this logic in io_u_queued_complete(), >> I >>>> think >>>>> that would be a safer alternative instead of near the callers. >>> >>> io_u_quisce, which calls io_u_queued_complete with an argument >>> of 1, includes this comment: >>> * and cur_depth is meaningless for sync engines. >>> >>> If that is invoked during sync traffic too, then putting this >>> change inside io_u_queued_complete might not work right. >> >> It's good enough for this use case. And it doesn't really matter if >> it's >> near the caller or in the function from this point of view, since >> there >> will be nothing (0) to complete for sync engines. By their very >> nature, >> they have nothing pending at that point. So I think the patch is fine >> as >> I sent out. > > I ran this version through similar tests and it works as well. Great thanks Rob, I committed that fix. -- Jens Axboe