summaryrefslogtreecommitdiffstats
path: root/block/Kconfig
diff options
context:
space:
mode:
authorVivek Goyal <vgoyal@redhat.com>2009-12-03 18:59:55 +0100
committerJens Axboe <jens.axboe@oracle.com>2009-12-03 19:28:53 +0100
commitae30c286553c91c49af5cbc0265a05a6543d0c52 (patch)
tree1dcb055e156ca9190d0da5bccf32a3a166e12d52 /block/Kconfig
parentblkio: Determine async workload length based on total number of queues (diff)
downloadlinux-ae30c286553c91c49af5cbc0265a05a6543d0c52.tar.xz
linux-ae30c286553c91c49af5cbc0265a05a6543d0c52.zip
blkio: Implement group_isolation tunable
o If a group is running only a random reader, then it will not have enough traffic to keep disk busy and we will reduce overall throughput. This should result in better latencies for random reader though. If we don't idle on random reader service tree, then this random reader will experience large latencies if there are other groups present in system with sequential readers running in these. o One solution suggested by corrado is that by default keep the random readers or sync-noidle workload in root group so that during one dispatch round we idle only once on sync-noidle tree. This means that all the sync-idle workload queues will be in their respective group and we will see service differentiation in those but not on sync-noidle workload. o Provide a tunable group_isolation. If set, this will make sure that even sync-noidle queues go in their respective group and we wait on these. This provides stronger isolation between groups but at the expense of throughput if group does not have enough traffic to keep the disk busy. o By default group_isolation = 0 Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block/Kconfig')
0 files changed, 0 insertions, 0 deletions