zpool import taking weeks ...

[Gomes do Vale Victor]

Hi


Le 15 janv. 2014 à 23:34, kpneal at pobox.com a écrit :

> On Wed, Jan 15, 2014 at 09:29:27AM +0100, Ulysse 31 wrote:
>> Thanks for the answer.
>> 
>> I was beginning to ... well ... have a little start of panic ^^'
>> The import still running but no real activity on disks : sometimes,
>> maybe something like each hour, there is some really brief led
>> activity on the hdd, but nothing more.
>> one thing that would be great is to have an overall percentage or just
>> counting of what is done or what is left ... for now i don't even know
>> if it's gonna end on the next 5 mins or on the next 5 weeks :s
>> So now since i have no real activity on the actual zpool import (the
>> last import started a week ago, it do not have go out of swap since i
>> added lot of swap (260G HDD swap)), should i just let it run, or make
>> a reboot and start over ?
> 
> Memory used by the ZFS DDT is (someone correct me if I'm wrong) kernel
> memory that I don't think is swappable. So adding more swap space won't
> help. (Again, correct me if I'm out of date or just wrong please.)
> 

Yes, it's kernel memory but appears as "wired" not as "used", and it does not change the fact that zpool import goes out of swap without the swap disk (tested and approved). With the disk memory is all (64Gb) marked as wired (kernel usage) plus 780Mo used in swap. 

> Worse, keeping track of swap space takes kernel memory for the bookkeeping.

Again, I have tested zpool import WITHOUT the disk, and it as gone "out of swap" (out of memory) since I added the disk it as taken all mem plus swap. Please read my first and my post .

> That memory for swap bookkeeping is memory that can't be used by ZFS. So
> the large swap device you added is only making the situation worse. This
> also implies that you'll get best results by not having any swap space
> at all during the problematic import. You can re-add it once the import
> is completed.
> 

I really don't know if ZFS can swap or not, what I know is that system and livecd goes out of memory on import.
One possible solution is simply ZFS takes all RAM leaving swap to user land ... But result is the same : machine crashes without it.


> -- 
> Kevin P. Neal                                http://www.pobox.com/~kpn/
> 
> Seen on bottom of IBM part number 1887724:
> DO NOT EXPOSE MOUSE PAD TO DIRECT SUNLIGHT FOR EXTENDED PERIODS OF TIME.