Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-05 Thread Christoph Anton Mitterer
On Tue, 2016-01-05 at 11:44 +0100, David Sterba wrote: > We have a full 32 bit number space, so multiples of power of 2 are > also > possible if that makes sense. Hmm that would make a maximum of 4GiB RAID chunks... perhaps we should reserve some of the higher bits for a multiplier, in case 4GiB wo

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-05 Thread David Sterba
On Sun, Jan 03, 2016 at 03:26:25AM +0100, Christoph Anton Mitterer wrote: > On Sun, 2016-01-03 at 09:37 +0800, Qu Wenruo wrote: > > And since you are making the stripe size configurable, then user is  > > responsible for any too large or too small stripe size setting. > That pops up the questions,

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-05 Thread David Sterba
On Wed, Dec 30, 2015 at 04:21:47PM -0500, Sanidhya Solanki wrote: > On Wed, 30 Dec 2015 17:17:22 +0100 > David Sterba wrote: > > > Let me note that a good reputation is also built from patch reviews > > (hint hint). > > Unfortunately, not too many patches coming in for BTRFS presently. > Mailing

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-05 Thread David Sterba
On Thu, Dec 31, 2015 at 08:46:36AM +0800, Qu Wenruo wrote: > > Let me note that a good reputation is also built from patch reviews > > (hint hint). > > I must admit I'm a bad reviewer. > As when I review something, I always has an eager to rewrite part or all > the patch to follow my idea, even i

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-02 Thread Christoph Anton Mitterer
On Sun, 2016-01-03 at 09:37 +0800, Qu Wenruo wrote: > And since you are making the stripe size configurable, then user is  > responsible for any too large or too small stripe size setting. That pops up the questions, which raid chunk sizes the kernel, respectively the userland tools should allow fo

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-02 Thread Qu Wenruo
On 01/02/2016 07:52 PM, Sanidhya Solanki wrote: On Tue, 29 Dec 2015 19:06:44 +0100 David Sterba wrote: In theory this is possible with current on-disk data structures. The stripe length is property of btrfs_chunk and changing it should be possible the same way we do other raid transformation

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2016-01-02 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 19:06:44 +0100 David Sterba wrote: > In theory this is possible with current on-disk data structures. The > stripe length is property of btrfs_chunk and changing it should be > possible the same way we do other raid transformations. The > implementation might be tricky at some

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Sanidhya Solanki
On Wed, 30 Dec 2015 17:17:22 +0100 David Sterba wrote: > Let me note that a good reputation is also built from patch reviews > (hint hint). Unfortunately, not too many patches coming in for BTRFS presently. Mailing list activity is down to 25-35 mails per day. Mostly feature and bug requests. I

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Sanidhya Solanki
On Wed, 30 Dec 2015 16:58:05 +0100 David Sterba wrote: > On Wed, Dec 30, 2015 at 06:15:23AM -0500, Sanidhya Solanki wrote: > > - Implement a way to do an in-place Stripe Length change. > > How are you going to implement that? I've suggested the balance filter > style of conversion, which is not

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Qu Wenruo
David Sterba wrote on 2015/12/30 17:17 +0100: On Wed, Dec 30, 2015 at 10:10:44PM +0800, Qu Wenruo wrote: Now I am on the same side of David. Which means a runtime interface to change them. (along with mkfs option) If provide some configurable features, then it should be able to be tuned at bo

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Christoph Anton Mitterer
On Wed, 2015-12-30 at 21:02 +, Duncan wrote: > For something like that, it'd pretty much /have/ to be done as COW, > at  > least at the chunk level, tho the address from the outside may stay > the  > same.  That's what balance already does, after all. Ah... of course,... it would be basically C

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Duncan
Christoph Anton Mitterer posted on Wed, 30 Dec 2015 21:00:11 +0100 as excerpted: > On Tue, 2015-12-29 at 19:06 +0100, David Sterba wrote: >> > Both open of course many questions (how to deal with crashes, >> > etc.)... >> > maybe having a look at how mdadm handles similar problems could be >> > wo

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Christoph Anton Mitterer
On Tue, 2015-12-29 at 19:06 +0100, David Sterba wrote: > > Both open of course many questions (how to deal with crashes, > > etc.)... > > maybe having a look at how mdadm handles similar problems could be > > worth. > > The crash consistency should remain, other than that we'd have to > enhance th

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Christoph Anton Mitterer
On Wed, 2015-12-30 at 22:10 +0800, Qu Wenruo wrote: > Or, just don't touch it until there is really enough user demand. I definitely think that there is demand... as I've written previously, when I did some benchmarking tests (though on MD and HW raid) then depending on the RAID chunk size, one got

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread David Sterba
On Wed, Dec 30, 2015 at 10:10:44PM +0800, Qu Wenruo wrote: > Now I am on the same side of David. > Which means a runtime interface to change them. (along with mkfs option) > > If provide some configurable features, then it should be able to be > tuned at both right time and mkfs time. > Or, just

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread David Sterba
On Wed, Dec 30, 2015 at 06:15:23AM -0500, Sanidhya Solanki wrote: > Only one problem. I do not run BTRFS on my systems nor do I have a > RAID setup, due to possessing a limited number of free drives. So, while > I may be able to code for it, I will not be able to test it. I will need > the communit

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Sanidhya Solanki
On Wed, 30 Dec 2015 22:10:44 +0800 Qu Wenruo wrote: > Understood now. Good. > I totally understand that implement ... to polish your > skill. That has got to be the most hilarious way I believe I have seen someone delegate a task. But it was effective. Only one problem. I do not run BTRFS on m

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Qu Wenruo
On 12/30/2015 05:54 PM, Sanidhya Solanki wrote: On Wed, 30 Dec 2015 19:59:16 +0800 Qu Wenruo wrote: Not really sure about the difference between 2 and 3. I should have made it clear before, I was asking the exact use case in mind when listing the choices. Option 2 would be for SysAdmins run

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Sanidhya Solanki
On Wed, 30 Dec 2015 19:59:16 +0800 Qu Wenruo wrote: > Not really sure about the difference between 2 and 3. I should have made it clear before, I was asking the exact use case in mind when listing the choices. Option 2 would be for SysAdmins running production software and configuring it as they

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Qu Wenruo
On 12/30/2015 02:39 PM, Sanidhya Solanki wrote: On Tue, 29 Dec 2015 18:06:11 +0100 David Sterba wrote: So you want to make the stripe size configurable?... As I see it there are 3 ways to do it: -Make it a compile time option that only configures it for a single system with any devices tha

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-30 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 18:06:11 +0100 David Sterba wrote: > So you want to make the stripe size configurable?... As I see it there are 3 ways to do it: -Make it a compile time option that only configures it for a single system with any devices that are added to the RAID. -Make it a runtime option t

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread Christoph Anton Mitterer
On Tue, 2015-12-29 at 16:44 +, Duncan wrote: > As I normally put it, btrfs is "definitely stabilizING, but not yet  > entirely stable and mature." [snip snap] And now... as a song please :D I'd also take a medieval rhyme ;-) Cheers, Chris. smime.p7s Description: S/MIME cryptographic signat

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 18:06:11 +0100 David Sterba wrote: > I don't know about all implications from changing the define to > sb->stripesize, also we want to define the allowed range etc. It would > be better to add more description to the patch. So, is the patch atleast somewhat usable and you jus

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread David Sterba
On Tue, Dec 29, 2015 at 05:26:28AM +0100, Christoph Anton Mitterer wrote: > On Mon, 2015-12-28 at 19:03 -0500, Sanidhya Solanki wrote: > > That sounds like an absolutely ghastly idea. > *G* and it probably is ;) > > > > Lots of potential for > > mistakes and potential data loss. I take up the of

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread David Sterba
On Tue, Dec 29, 2015 at 06:15:12AM -0500, Sanidhya Solanki wrote: > On Tue, 29 Dec 2015 14:39:07 +0100 > David Sterba wrote: > > > The stripe size depends on how the filesystem was made, at the moment > > the stripesize parameter is missing from mkfs. The kernel module > > should support all size

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread Duncan
Christoph Anton Mitterer posted on Tue, 29 Dec 2015 16:32:59 +0100 as excerpted: >> From Documentation/filesystems/BTRFS.txt: >> Btrfs is under heavy development, and is not suitable for any uses >> other than benchmarking and review. > Well I guess now it's time for Duncan's usual "stable or not

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread Christoph Anton Mitterer
On Mon, 2015-12-28 at 21:23 -0500, Sanidhya Solanki wrote: > From Documentation/filesystems/BTRFS.txt: > Btrfs is under heavy development, and is not suitable for > any uses other than benchmarking and review. Well I guess now it's time for Duncan's usual "stable or not" talk (@Duncan, I think by n

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 14:39:07 +0100 David Sterba wrote: > The stripe size depends on how the filesystem was made, at the moment > the stripesize parameter is missing from mkfs. The kernel module > should support all sizes at runtime, so it's not a compile-time > option. No good? I will try and re

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-29 Thread David Sterba
On Mon, Dec 28, 2015 at 07:24:11AM -0500, Sanidhya Solanki wrote: > An option to select the RAID Stripe size is made > available in the BTRFS Filesystem, via an option > in the BTRFS Config setup, with minimal change > to the existing code base. The stripe size depends on how the filesystem was ma

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 07:03:11 +0100 Christoph Anton Mitterer wrote: > On Mon, 2015-12-28 at 20:31 -0500, Sanidhya Solanki wrote: > > What is your experience like about running a production system on > > what > > is essentially a beta product? Crashes? > What do you mean? btrfs? I'm not yet running

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Christoph Anton Mitterer
On Mon, 2015-12-28 at 20:31 -0500, Sanidhya Solanki wrote: > What is your experience like about running a production system on > what > is essentially a beta product? Crashes? What do you mean? btrfs? I'm not yet running it in production (there was a subthread recently, where I've explained a bit m

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 05:26:28 +0100 Christoph Anton Mitterer wrote: > I spoke largely from the user/admin side,... running a quite big > storage Tier-2, we did many IO benchmarks over time (with different > hardware RAID controllers) and also as our IO patterns changed over > time... > The result

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Christoph Anton Mitterer
On Mon, 2015-12-28 at 19:03 -0500, Sanidhya Solanki wrote: > That sounds like an absolutely ghastly idea. *G* and it probably is ;) > Lots of potential for > mistakes and potential data loss. I take up the offer to implement > such a feature.  > Only question is should it be in-place replacement

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 04:42:08 +0100 Christoph Anton Mitterer wrote: > On Mon, 2015-12-28 at 16:43 -0500, Sanidhya Solanki wrote: > May get even much more complicated, if reshaping (i.e. conversion from > one chunk size to another) should get implemented as well... That sounds like an absolutely g

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Christoph Anton Mitterer
On Mon, 2015-12-28 at 16:43 -0500, Sanidhya Solanki wrote: > Apologies, it appears I did misunderstand. That should be possible, > though slightly complicated. I will try to get that done. May get even much more complicated, if reshaping (i.e. conversion from one chunk size to another) should get i

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Sanidhya Solanki
On Tue, 29 Dec 2015 02:21:09 +0100 Christoph Anton Mitterer wrote: > On Mon, 2015-12-28 at 15:38 -0500, Sanidhya Solanki wrote: > > > Shouldn't that rather eventually become configurable per > > > filesystem? > > Don't know. It was in the BTRFS File todo list, hence the > > BTRFS-specific patch.

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Christoph Anton Mitterer
On Mon, 2015-12-28 at 15:38 -0500, Sanidhya Solanki wrote: > > Shouldn't that rather eventually become configurable per > > filesystem? > Don't know. It was in the BTRFS File todo list, hence the > BTRFS-specific patch. Uhm you misunderstood me =) I meant, configurable per instance of a btrfs file

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Sanidhya Solanki
On Mon, 28 Dec 2015 23:19:55 +0100 Christoph Anton Mitterer wrote: > On Mon, 2015-12-28 at 07:24 -0500, Sanidhya Solanki wrote: > > An option to select the RAID Stripe size is made > > available in the BTRFS Filesystem, via an option > > in the BTRFS Config setup > Shouldn't that rather eventuall

Re: [PATCH] BTRFS: Adds an option to select RAID Stripe size

2015-12-28 Thread Christoph Anton Mitterer
On Mon, 2015-12-28 at 07:24 -0500, Sanidhya Solanki wrote: > An option to select the RAID Stripe size is made > available in the BTRFS Filesystem, via an option > in the BTRFS Config setup Shouldn't that rather eventually become configurable per filesystem? Cheers, Chris. smime.p7s Description: S