Messages in this thread | | | Subject | Re: [PATCH 2/7] mmc: Don't use PF_MEMALLOC | From | Peter Zijlstra <> | Date | Tue, 17 Nov 2009 21:47:06 +0100 |
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On Tue, 2009-11-17 at 21:51 +0900, Minchan Kim wrote: > I think it's because mempool reserves memory. > (# of I/O issue\0 is hard to be expected. > How do we determine mempool size of each block driver? > For example, maybe, server use few I/O for nand. > but embedded system uses a lot of I/O.
No, you scale the mempool to the minimum amount required to make progress -- this includes limiting the 'concurrency' when handing out mempool objects.
If you run into such tight corners often enough to notice it, there's something else wrong.
I fully agree with ripping out PF_MEMALLOC from pretty much everything, including the VM, getting rid of the various abuse outside of the VM seems like a very good start.
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