Re: A review of dm-writeboost

2013-10-20 Thread Dave Chinner
On Sat, Oct 19, 2013 at 07:59:55PM +0900, Akira Hayakawa wrote: > Dave, > > # -EIO retuned corrupts XFS > I turned up > lockdep, frame pointer, xfs debug > and also changed to 3.12.0-rc5 from rc1. > > What's changed is that > the problem we discussed in previous mails > *never* reproduce. > >

Re: A review of dm-writeboost

2013-10-20 Thread Dave Chinner
On Sat, Oct 19, 2013 at 07:59:55PM +0900, Akira Hayakawa wrote: Dave, # -EIO retuned corrupts XFS I turned up lockdep, frame pointer, xfs debug and also changed to 3.12.0-rc5 from rc1. What's changed is that the problem we discussed in previous mails *never* reproduce. However, if I

Re: A review of dm-writeboost

2013-10-19 Thread Akira Hayakawa
Dave, # -EIO retuned corrupts XFS I turned up lockdep, frame pointer, xfs debug and also changed to 3.12.0-rc5 from rc1. What's changed is that the problem we discussed in previous mails *never* reproduce. However, if I turn off the lockdep only it hangs up by setting blockup to 1 and then to 0

Re: A review of dm-writeboost

2013-10-19 Thread Akira Hayakawa
Dave, # -EIO retuned corrupts XFS I turned up lockdep, frame pointer, xfs debug and also changed to 3.12.0-rc5 from rc1. What's changed is that the problem we discussed in previous mails *never* reproduce. However, if I turn off the lockdep only it hangs up by setting blockup to 1 and then to 0

Re: A review of dm-writeboost

2013-10-16 Thread Dave Chinner
On Wed, Oct 16, 2013 at 09:17:40PM +0900, Akira Hayakawa wrote: > Dave > > > XFS shuts down because you've returned EIO to a log IO. That's a > > fatal error. If you do the same to an ext4 journal write, it will do > > the equivalent of shut down (e.g. complain and turn read-only). > You mean

Re: A review of dm-writeboost

2013-10-16 Thread Akira Hayakawa
Dave > XFS shuts down because you've returned EIO to a log IO. That's a > fatal error. If you do the same to an ext4 journal write, it will do > the equivalent of shut down (e.g. complain and turn read-only). You mean block device should not return -EIO anyway if it doesn't want XFS to suddenly

Re: A review of dm-writeboost

2013-10-16 Thread Dave Chinner
On Wed, Oct 16, 2013 at 07:34:38PM +0900, Akira Hayakawa wrote: > Dave > > > Akira, can you please post the entire set of messages you are > > getting when XFS showing problems? That way I can try to confirm > > whether it's a regression in XFS or something else. > > Environment: > - The kernel

Re: A review of dm-writeboost

2013-10-16 Thread Akira Hayakawa
Dave > Akira, can you please post the entire set of messages you are > getting when XFS showing problems? That way I can try to confirm > whether it's a regression in XFS or something else. Environment: - The kernel version is 3.12-rc1 - The debuggee is a KVM virtual machine equipped with 8

Re: A review of dm-writeboost

2013-10-16 Thread Dave Chinner
[cc x...@oss.sgi.com] On Tue, Oct 15, 2013 at 08:01:45PM -0400, Mikulas Patocka wrote: > On Mon, 14 Oct 2013, Akira Hayakawa wrote: > > But, XFS stalls ... > > --- > > For testing, > > I manually turns `blockup` to 1 > > when compiling Ruby is in progress > > on XFS on a

Re: A review of dm-writeboost

2013-10-16 Thread Dave Chinner
[cc x...@oss.sgi.com] On Tue, Oct 15, 2013 at 08:01:45PM -0400, Mikulas Patocka wrote: On Mon, 14 Oct 2013, Akira Hayakawa wrote: But, XFS stalls ... --- For testing, I manually turns `blockup` to 1 when compiling Ruby is in progress on XFS on a writeboost device.

Re: A review of dm-writeboost

2013-10-16 Thread Akira Hayakawa
Dave Akira, can you please post the entire set of messages you are getting when XFS showing problems? That way I can try to confirm whether it's a regression in XFS or something else. Environment: - The kernel version is 3.12-rc1 - The debuggee is a KVM virtual machine equipped with 8 vcpus.

Re: A review of dm-writeboost

2013-10-16 Thread Dave Chinner
On Wed, Oct 16, 2013 at 07:34:38PM +0900, Akira Hayakawa wrote: Dave Akira, can you please post the entire set of messages you are getting when XFS showing problems? That way I can try to confirm whether it's a regression in XFS or something else. Environment: - The kernel version is

Re: A review of dm-writeboost

2013-10-16 Thread Akira Hayakawa
Dave XFS shuts down because you've returned EIO to a log IO. That's a fatal error. If you do the same to an ext4 journal write, it will do the equivalent of shut down (e.g. complain and turn read-only). You mean block device should not return -EIO anyway if it doesn't want XFS to suddenly shut

Re: A review of dm-writeboost

2013-10-16 Thread Dave Chinner
On Wed, Oct 16, 2013 at 09:17:40PM +0900, Akira Hayakawa wrote: Dave XFS shuts down because you've returned EIO to a log IO. That's a fatal error. If you do the same to an ext4 journal write, it will do the equivalent of shut down (e.g. complain and turn read-only). You mean block device

Re: A review of dm-writeboost

2013-10-15 Thread Akira Hayakawa
Mikulas, > I/Os shouldn't be returned with -ENOMEM. If they are, you can treat it as > a hard error. It seems to be blkdev_issue_discard returns -ENOMEM when bio_alloc fails, for example. Waiting for a second and we can alloc the memory is my idea for handling -ENOMEM returned. > Blocking I/O

Re: A review of dm-writeboost

2013-10-15 Thread Mikulas Patocka
On Mon, 14 Oct 2013, Akira Hayakawa wrote: > Hi, DM Guys > > I suppose I have finished the tasks to > answer Mikulas's pointing outs. > So, let me update the progress report. > > The code is updated now on my Github repo. > Checkout the develop branch to avail > the latest source code. > >

Re: A review of dm-writeboost

2013-10-15 Thread Mikulas Patocka
On Mon, 14 Oct 2013, Akira Hayakawa wrote: Hi, DM Guys I suppose I have finished the tasks to answer Mikulas's pointing outs. So, let me update the progress report. The code is updated now on my Github repo. Checkout the develop branch to avail the latest source code. Compilation

Re: A review of dm-writeboost

2013-10-15 Thread Akira Hayakawa
Mikulas, I/Os shouldn't be returned with -ENOMEM. If they are, you can treat it as a hard error. It seems to be blkdev_issue_discard returns -ENOMEM when bio_alloc fails, for example. Waiting for a second and we can alloc the memory is my idea for handling -ENOMEM returned. Blocking I/O

Re: A review of dm-writeboost

2013-10-14 Thread Akira Hayakawa
Hi, DM Guys I suppose I have finished the tasks to answer Mikulas's pointing outs. So, let me update the progress report. The code is updated now on my Github repo. Checkout the develop branch to avail the latest source code. Compilation Status -- First, compilation status.

Re: A review of dm-writeboost

2013-10-14 Thread Akira Hayakawa
Hi, DM Guys I suppose I have finished the tasks to answer Mikulas's pointing outs. So, let me update the progress report. The code is updated now on my Github repo. Checkout the develop branch to avail the latest source code. Compilation Status -- First, compilation status.

Re: A review of dm-writeboost

2013-10-09 Thread Akira Hayakawa
Mikulas, > Next, you need to design some locking - which variables are protected by > which locks. If you use shared variables without locks, you need to use > memory barriers (it is harder to design code using memory barriers than > locks). First I will explain the locking and the shared

Re: A review of dm-writeboost

2013-10-09 Thread Akira Hayakawa
Mikulas, Next, you need to design some locking - which variables are protected by which locks. If you use shared variables without locks, you need to use memory barriers (it is harder to design code using memory barriers than locks). First I will explain the locking and the shared

Re: A review of dm-writeboost

2013-10-07 Thread Mikulas Patocka
On Sun, 6 Oct 2013, Akira Hayakawa wrote: > Mikulas, > > Thank you for your reviewing. > > I will reply to polling issue first. > For the rest, I will reply later. > > > Polling for state > > - > > > > Some of the kernel threads that you spawn poll for data in one-second >

Re: A review of dm-writeboost

2013-10-07 Thread Mikulas Patocka
On Sun, 6 Oct 2013, Akira Hayakawa wrote: Mikulas, Thank you for your reviewing. I will reply to polling issue first. For the rest, I will reply later. Polling for state - Some of the kernel threads that you spawn poll for data in one-second interval - see

Re: A review of dm-writeboost

2013-10-06 Thread Akira Hayakawa
Mikulas, Thank you for your reviewing. I will reply to polling issue first. For the rest, I will reply later. > Polling for state > - > > Some of the kernel threads that you spawn poll for data in one-second > interval - see migrate_proc, modulator_proc, recorder_proc,

Re: A review of dm-writeboost

2013-10-06 Thread Akira Hayakawa
Mikulas, Thank you for your reviewing. I will reply to polling issue first. For the rest, I will reply later. Polling for state - Some of the kernel threads that you spawn poll for data in one-second interval - see migrate_proc, modulator_proc, recorder_proc, sync_proc.