From ae29d6c64bd8d55873a2cb1df50ae4321b497447 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Fri, 5 Apr 2013 11:32:20 +0200 Subject: block: keep I/O throttling slice time constant MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It is not necessary to adjust the slice time at runtime. We already extend the current slice in order to carry over accounting into the next slice. Changing the actual slice time value introduces oscillations. The guest may experience large changes in throughput or IOPS from one moment to the next when slice times are adjusted. Reported-by: BenoƮt Canet Signed-off-by: Stefan Hajnoczi Tested-By: Benoit Canet Signed-off-by: Kevin Wolf --- blockdev.c | 1 - 1 file changed, 1 deletion(-) (limited to 'blockdev.c') diff --git a/blockdev.c b/blockdev.c index 8cdc9ce16a..6dc999d802 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1069,7 +1069,6 @@ void qmp_block_set_io_throttle(const char *device, int64_t bps, int64_t bps_rd, } bs->io_limits = io_limits; - bs->slice_time = BLOCK_IO_SLICE_TIME; if (!bs->io_limits_enabled && bdrv_io_limits_enabled(bs)) { bdrv_io_limits_enable(bs); -- cgit v1.2.3