Messages in this thread | | | Date | Thu, 6 Jan 2005 05:59:32 +0100 | From | Andrea Arcangeli <> | Subject | Re: [PATCH][5/?] count writeback pages in nr_scanned |
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On Wed, Jan 05, 2005 at 08:47:06PM -0800, Andrew Morton wrote: > That's my point. blk_congestion_wait() will always sleep, regardless of
Since I've no pending bugs at all with the mainline codebase I rate this just a theoretical issue: but even sleeping for a fixed amount of time is unreliable there, for example if the storage is very slow. That's why using io_schedule_timeout for that isn't going to be a fix.
The fix is very simple and it is to call wait_on_page_writeback on one of the pages under writeback. That guarantees some _writeback_ progress has been made before retrying. That way some random direct-io or a too short timeout, can't cause malfunction. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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