Re: [OpenIndiana-discuss] 4k sectors again

2012-02-15 Thread Roy Sigurd Karlsbakk
  Seems most drives are moving to 512-bytes-on-4k-sectors these days,
  as
  with the new 7K4000 drives from Hitachi. I saw a patch for zpool
  some time
  back, fixing ashift, but that's all. Is there an official fix
  somewhere?
  What do people with 4k drives do?
 
 
 If the drive reports its block size as 4K ZFS will do the right thing
 already. Only drives that lie about the actual block size and report
 512
 bytes are problematic.
 For such drives the technique I found useful is to create a pool on
 some
 other devices that are true 4K and then replace the devices one by one
 with
 the problematic drives.
 COMSTAR comes really handy for such a trick. Also Linux ZFS let you
 specify
 ashift manually during pool creation.

Basically, *all* drives lie about this these days, so we'd better fix it in 
software instead of hoping drives and politicians stop lying.

So I guess what must be done, then, is to port the fix from Linux ZFS to 
Illumos/OpenIndiana? Installing this system with linux zfs and then move to 
openindiana isn't very amusing...

Any idea how much code this is? Or is it the old patch that was rejected a year 
ago or so?

Vennlige hilsener / Best regards

roy
--
Roy Sigurd Karlsbakk
(+47) 97542685
r...@karlsbakk.net
http://blogg.karlsbakk.net/
--
I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er 
et elementært imperativ for alle pedagoger å unngå eksessiv anvendelse av 
idiomer med fremmed opprinnelse. I de fleste tilfeller eksisterer adekvate og 
relevante synonymer på norsk.

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Re: [OpenIndiana-discuss] 4k sectors again

2012-02-15 Thread Jonathan Adams
Umm, no, not all drives do this, it is relatively easy to get hold of
drives that aren't EARS ... you are just better off going for
non-consumer drives.

Will post links if you need them.

Jon

On 15 February 2012 08:24, Roy Sigurd Karlsbakk r...@karlsbakk.net wrote:
  Seems most drives are moving to 512-bytes-on-4k-sectors these days,
  as
  with the new 7K4000 drives from Hitachi. I saw a patch for zpool
  some time
  back, fixing ashift, but that's all. Is there an official fix
  somewhere?
  What do people with 4k drives do?
 

 If the drive reports its block size as 4K ZFS will do the right thing
 already. Only drives that lie about the actual block size and report
 512
 bytes are problematic.
 For such drives the technique I found useful is to create a pool on
 some
 other devices that are true 4K and then replace the devices one by one
 with
 the problematic drives.
 COMSTAR comes really handy for such a trick. Also Linux ZFS let you
 specify
 ashift manually during pool creation.

 Basically, *all* drives lie about this these days, so we'd better fix it in 
 software instead of hoping drives and politicians stop lying.

 So I guess what must be done, then, is to port the fix from Linux ZFS to 
 Illumos/OpenIndiana? Installing this system with linux zfs and then move to 
 openindiana isn't very amusing...

 Any idea how much code this is? Or is it the old patch that was rejected a 
 year ago or so?

 Vennlige hilsener / Best regards

 roy
 --
 Roy Sigurd Karlsbakk
 (+47) 97542685
 r...@karlsbakk.net
 http://blogg.karlsbakk.net/
 --
 I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det 
 er et elementært imperativ for alle pedagoger å unngå eksessiv anvendelse av 
 idiomer med fremmed opprinnelse. I de fleste tilfeller eksisterer adekvate og 
 relevante synonymer på norsk.

 ___
 OpenIndiana-discuss mailing list
 OpenIndiana-discuss@openindiana.org
 http://openindiana.org/mailman/listinfo/openindiana-discuss

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[OpenIndiana-discuss] 4k sectors again

2012-02-14 Thread Roy Sigurd Karlsbakk
Hi all

Seems most drives are moving to 512-bytes-on-4k-sectors these days, as with the 
new 7K4000 drives from Hitachi. I saw a patch for zpool some time back, fixing 
ashift, but that's all. Is there an official fix somewhere? What do people with 
4k drives do?

-- 
Vennlige hilsener / Best regards

roy
--
Roy Sigurd Karlsbakk
(+47) 97542685
r...@karlsbakk.net
http://blogg.karlsbakk.net/
--
I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er 
et elementært imperativ for alle pedagoger å unngå eksessiv anvendelse av 
idiomer med fremmed opprinnelse. I de fleste tilfeller eksisterer adekvate og 
relevante synonymer på norsk.

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Re: [OpenIndiana-discuss] 4k sectors again

2012-02-14 Thread Cyril Plisko
On Tue, Feb 14, 2012 at 10:53 PM, Roy Sigurd Karlsbakk 
r...@karlsbakk.netwrote:

 Hi all

 Seems most drives are moving to 512-bytes-on-4k-sectors these days, as
 with the new 7K4000 drives from Hitachi. I saw a patch for zpool some time
 back, fixing ashift, but that's all. Is there an official fix somewhere?
 What do people with 4k drives do?


If the drive reports its block size as 4K ZFS will do the right thing
already. Only drives that lie about the actual block size and report 512
bytes are problematic.
For such drives the technique I found useful is to create a pool on some
other devices that are true 4K and then replace the devices one by one with
the problematic drives.
COMSTAR comes really handy for such a trick. Also Linux ZFS let you specify
ashift manually during pool creation.


-- 
Regards,
Cyril
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