On 12/30/2013 7:19 AM, Roger Willcocks wrote:
>
> On 30 Dec 2013, at 01:55, Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx> wrote:
>
>> On 12/29/2013 3:50 AM, Dave Chinner wrote:
>> ...
>>> I think you are forgetting that developer time is *expensive* and
>>> *scarce*. This is essentially a solved problem: An SSD in a USB3
>>> enclosure as a temporary swap device is by far the most cost
>>> effective way to make repair scale to arbitrary amounts of metadata.
>>> It certainly scales far better than developer time and testing
>>> resources...
>>
>> Now this is an interesting idea Dave. I hadn't considered temporary
>> swap. Would USB be reliable enough for this? I've seen lots problem
>> reports with folks using USB storage with Linux, random disconnections
>> and what not.
>>
>
> I'll just chip in here and mention that we get around this problem by
> exporting the broken xfs volume over iscsi and run xfs-repair on another
> machine with more memory / swap space.
Another interesting, actually excellent idea Roger. So Arkadiusz could
get by with just one set of SSDs. Pulling ~40 GB of metadata over GbE
iSCSI should take only about 7 minutes of wire time, assuming his
hosts/net can sustain 100 MB/s.
--
Stan
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