Re: [PATCH] zram: set zram bio priority to REQ_PRIO.
From: Sergey Senozhatsky <senozhatsky@chromium.org>
Date: 2023-07-18 07:49:43
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lkml
Cc-ing Christoph On (23/07/18 15:11), Huanpeng Xin wrote:
When the system memory pressure is high, set zram bio priority to REQ_PRIO can quickly swap zarm's memory to backing device,
read_from_bdev_async() does the opposite. [..]
quoted hunk ↗ jump to hunk
@@ -616,7 +616,7 @@ static int read_from_bdev_async(struct zram *zram, struct bio_vec *bvec, { + bio = bio_alloc(zram->bdev, 1, parent ? parent->bi_opf : REQ_OP_READ | REQ_PRIO, GFP_NOIO);
[..]
quoted hunk ↗ jump to hunk
@@ -746,7 +746,7 @@ static ssize_t writeback_store(struct device *dev,... bio_init(&bio, zram->bdev, &bio_vec, 1, - REQ_OP_WRITE | REQ_SYNC); + REQ_OP_WRITE | REQ_SYNC | REQ_PRIO);
In general, zram writeback is not for situations when the system is critically low on memory; performance there is not that important, so I'm not sure whether we want to boost requests' priorities.