[lkml]   [2007]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 0/4] Improve swap page error handling
Richard Purdie wrote:

>>No, not this way, I'm afraid. Sorry, I don't remember the prior
>>discussion on LKML, must have flooded past when my attention was
> I think you were cc'd on some of it but you never commented. Anyhow,
> I've reworked this patch series based on your comments. The hints were
> appreciated, thanks. This was the way I'd originally hoped to be able to
> work things, I just couldn't find the right way to do it.

IMO it seems a bit complex for so small a benefit. Last time I was
working on this, I thought it would be almost as good to do something
simple like stop trying to write out the page if PG_error is set (and
clear that bit in delete_from_swap_cache or try_to_unusesomewhere).
This way the admin could swapoff and scan the swap device at some

>>Is it worth doing this at all? Probably, but I've no experience
>>whatsoever of swap write errors, so it's hard for me to judge: my
>>guess is that many cases would turn out to be software errors (e.g.
>>lower level needing more memory to perform the write). But you'd
>>be right to counter: let's assume they're hardware errors, and
>>then fix up any software errors when reported.
> I have a swap block driver where hardware write errors are more likely
> and hence have a need to handle them more gracefully than IO loops. It
> seems like a good idea to avoid the IO loops anyway.
>>If it is worth doing this, then you'll need to add code to write
>>back the swap header, to note the bad pages permanently: you may
>>well have been waiting to see what reception the patches so far
>>get, before embarking on that.
> You can't proceed to do that until you're able to identify the bad pages
> so this would be a necessary first step towards that, yes.

Agreed here, FWIW. I think that might be just as well done in


SUSE Labs, Novell Inc.
Send instant messages to your online friends

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2007-01-11 00:05    [W:0.050 / U:0.732 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site