Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 8:37pm -0500, Mike Snitzer wrote: > On Fri, Jan 12 2018 at 8:00pm -0500, > Bart Van Assche wrote: > > > On Fri, 2018-01-12 at 19:52 -0500, Mike Snitzer wrote: > > > It was 50 ms before it was 100 ms. No real explaination for

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Sat, Jan 13 2018 at 10:04am -0500, Ming Lei wrote: > On Fri, Jan 12, 2018 at 05:31:17PM -0500, Mike Snitzer wrote: > > > > Ming or Jens: might you be able to shed some light on how dm-mpath > > would/could set BLK_MQ_S_SCHED_RESTART? A new function added that can > >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12, 2018 at 05:31:17PM -0500, Mike Snitzer wrote: > On Fri, Jan 12 2018 at 1:54pm -0500, > Bart Van Assche wrote: > > > On Fri, 2018-01-12 at 13:06 -0500, Mike Snitzer wrote: > > > OK, you have the stage: please give me a pointer to your best > > >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12, 2018 at 06:54:49PM +, Bart Van Assche wrote: > On Fri, 2018-01-12 at 13:06 -0500, Mike Snitzer wrote: > > OK, you have the stage: please give me a pointer to your best > > explaination of the several. > > Since the previous discussion about this topic occurred more than a

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 8:00pm -0500, Bart Van Assche wrote: > On Fri, 2018-01-12 at 19:52 -0500, Mike Snitzer wrote: > > It was 50 ms before it was 100 ms. No real explaination for these > > values other than they seem to make Bart's IB SRP testbed happy? > > But that

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, 2018-01-12 at 19:52 -0500, Mike Snitzer wrote: > It was 50 ms before it was 100 ms. No real explaination for these > values other than they seem to make Bart's IB SRP testbed happy? But that constant was not introduced by me in the dm code. See e.g. the following commits: commit

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 2:53pm -0500, Elliott, Robert (Persistent Memory) wrote: > > > > -Original Message- > > From: linux-block-ow...@vger.kernel.org [mailto:linux-block- > > ow...@vger.kernel.org] On Behalf Of Bart Van Assche > ... > > The intention of commit

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 6:42pm -0500, Bart Van Assche wrote: > On Fri, 2018-01-12 at 18:17 -0500, Mike Snitzer wrote: > > @@ -1570,7 +1570,10 @@ static int multipath_end_io(struct dm_target *ti, > > struct request *clone, > > if (error && blk_path_error(error)) { > >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, 2018-01-12 at 18:17 -0500, Mike Snitzer wrote: > @@ -1570,7 +1570,10 @@ static int multipath_end_io(struct dm_target *ti, > struct request *clone, > if (error && blk_path_error(error)) { > struct multipath *m = ti->private; > > - r = DM_ENDIO_REQUEUE; > +

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 1:54pm -0500, Bart Van Assche wrote: > The intention of commit 6077c2d706097c0 was to address the last mentioned > case. It may be possible to move the delayed queue rerun from the > dm_queue_rq() into dm_requeue_original_request(). But I think it

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 1:54pm -0500, Bart Van Assche wrote: > On Fri, 2018-01-12 at 13:06 -0500, Mike Snitzer wrote: > > OK, you have the stage: please give me a pointer to your best > > explaination of the several. > > Since the previous discussion about this topic

RE: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

> -Original Message- > From: linux-block-ow...@vger.kernel.org [mailto:linux-block- > ow...@vger.kernel.org] On Behalf Of Bart Van Assche ... > The intention of commit 6077c2d706097c0 was to address the last mentioned > case. It may be possible to move the delayed queue rerun from the >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 1:54pm -0500, Bart Van Assche wrote: > On Fri, 2018-01-12 at 13:06 -0500, Mike Snitzer wrote: > > OK, you have the stage: please give me a pointer to your best > > explaination of the several. > > Since the previous discussion about this topic

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, 2018-01-12 at 13:06 -0500, Mike Snitzer wrote: > OK, you have the stage: please give me a pointer to your best > explaination of the several. Since the previous discussion about this topic occurred more than a month ago it could take more time to look up an explanation than to explain it

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 12:46pm -0500, Bart Van Assche wrote: > On Fri, 2018-01-12 at 12:40 -0500, Mike Snitzer wrote: > > You've not explained it many times. > > That's not correct. I have already several times posted a detailed and easy > to understand explanation OK,

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, 2018-01-12 at 12:40 -0500, Mike Snitzer wrote: > You've not explained it many times. That's not correct. I have already several times posted a detailed and easy to understand explanation > We cannot get a straight answer from you. That is a gross and incorrect statement. Please calm

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, Jan 12 2018 at 12:26pm -0500, Bart Van Assche wrote: > On Fri, 2018-01-12 at 12:18 -0500, Mike Snitzer wrote: > > This is going upstream for 4.16: > >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Fri, 2018-01-12 at 12:18 -0500, Mike Snitzer wrote: > This is going upstream for 4.16: > https://git.kernel.org/pub/scm/linux/kernel/git/snitzer/linux.git/commit/?h=dm-4.16=5b18cff4baedde77e0d69bd62a13ae78f9488d89 That is really gross. I have explained many times in detail on the dm-devel list

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11 2018 at 10:33pm -0500, Ming Lei wrote: > On Thu, Jan 11, 2018 at 08:57:21PM -0500, Mike Snitzer wrote: > > On Thu, Jan 11 2018 at 8:42pm -0500, > > Ming Lei wrote: > > > > > On Thu, Jan 11, 2018 at 10:37:37PM +, Bart Van Assche

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11, 2018 at 08:57:21PM -0500, Mike Snitzer wrote: > On Thu, Jan 11 2018 at 8:42pm -0500, > Ming Lei wrote: > > > On Thu, Jan 11, 2018 at 10:37:37PM +, Bart Van Assche wrote: > > > On Thu, 2018-01-11 at 17:07 -0500, Mike Snitzer wrote: > > > > Bart, if for

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11 2018 at 8:42pm -0500, Ming Lei wrote: > On Thu, Jan 11, 2018 at 10:37:37PM +, Bart Van Assche wrote: > > On Thu, 2018-01-11 at 17:07 -0500, Mike Snitzer wrote: > > > Bart, if for some reason we regress for some workload you're able to > > > more readily

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11 2018 at 6:27pm -0500, Bart Van Assche wrote: > On Thu, 2018-01-11 at 17:58 -0500, Mike Snitzer wrote: > > The changes are pretty easy to review. This notion that these changes > > are problematic rings very hollow given your lack of actual numbers (or > >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11, 2018 at 10:37:37PM +, Bart Van Assche wrote: > On Thu, 2018-01-11 at 17:07 -0500, Mike Snitzer wrote: > > Bart, if for some reason we regress for some workload you're able to > > more readily test we can deal with it. But I'm too encouraged by Ming's > > performance

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, 2018-01-11 at 17:58 -0500, Mike Snitzer wrote: > The changes are pretty easy to review. This notion that these changes > are problematic rings very hollow given your lack of actual numbers (or > some other concerning observation rooted in testing fact) to back up > your position. It's

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11 2018 at 5:37pm -0500, Bart Van Assche wrote: > On Thu, 2018-01-11 at 17:07 -0500, Mike Snitzer wrote: > > Bart, if for some reason we regress for some workload you're able to > > more readily test we can deal with it. But I'm too encouraged by Ming's > >

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, 2018-01-11 at 17:07 -0500, Mike Snitzer wrote: > Bart, if for some reason we regress for some workload you're able to > more readily test we can deal with it. But I'm too encouraged by Ming's > performance improvements to hold these changes back any further. Sorry Mike but I think Ming's

Re: [PATCH V3 0/5] dm-rq: improve sequential I/O performance

On Thu, Jan 11 2018 at 1:01am -0500, Ming Lei wrote: > Hi Guys, > > The 1st patch removes the workaround of blk_mq_delay_run_hw_queue() in > case of requeue, this way isn't necessary, and more worse, it makes > BLK_MQ_S_SCHED_RESTART not working, and degarde I/O

[PATCH V3 0/5] dm-rq: improve sequential I/O performance

Hi Guys, The 1st patch removes the workaround of blk_mq_delay_run_hw_queue() in case of requeue, this way isn't necessary, and more worse, it makes BLK_MQ_S_SCHED_RESTART not working, and degarde I/O performance. The 2nd patch return DM_MAPIO_REQUEUE to dm-rq if underlying request allocation