Messages in this thread | | | Subject | Re: [dm-devel] dm: Make MIN_IOS, et al, tunable via sysctl. | From | Frank Mayhar <> | Date | Mon, 19 Aug 2013 10:54:05 -0700 |
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On Mon, 2013-08-19 at 10:00 -0400, Mike Snitzer wrote: > Performance isn't the concern. The concern is: does DM allow for > forward progress if the system's memory is completely exhausted? > > This is why request-based has such an extensive reserve, because it > needs to account for cloning the largest possible request that comes in > (with multiple bios).
Thanks for the response. In our particular case, I/O will be file system based and over a network, which makes it pretty easy for us to be sure that large I/Os never happen. That notwithstanding, however, as you said it just seems reasonable to make these values configurable.
I'm also looking at making some similar constants in dm-verity and dm-bufio configurable in the same way and for similar reasons. -- Frank Mayhar 310-460-4042
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