From: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
To: Jens Axboe <axboe@kernel.dk>, Vivek Goyal <vgoyal@redhat.com>
Cc: Corrado Zoccolo <czoccolo@gmail.com>,
Chad Talbott <ctalbott@google.com>,
Nauman Rafique <nauman@google.com>,
Divyesh Shah <dpshah@google.com>,
linux kernel mailing list <linux-kernel@vger.kernel.org>
Subject: [PATCH 0/8 v2] Introduce CFQ group hierarchical scheduling and "use_hierarchy" interface
Date: Mon, 13 Dec 2010 09:44:10 +0800 [thread overview]
Message-ID: <4D057A6A.8060000@cn.fujitsu.com> (raw)
In-Reply-To: <4CE2718C.6010406@kernel.dk>
[-- Attachment #1: Type: text/plain, Size: 2241 bytes --]
Hi
Previously, I posted a patchset to add support of CFQ group hierarchical scheduling
in the way that it puts all CFQ queues in a hidden group and schedules with other
CFQ group under their parent. The patchset is available here,
http://lkml.org/lkml/2010/8/30/30
Vivek think this approach isn't so instinct that we should treat CFQ queues
and groups at the same level. Here is the new approach for hierarchical
scheduling based on Vivek's suggestion. The most big change of CFQ is that
it gets rid of cfq_slice_offset logic, and makes use of vdisktime for CFQ
queue scheduling just like CFQ group does. But I still give cfqq some jump
in vdisktime based on ioprio, thanks for Vivek to point out this. Now CFQ
queue and CFQ group uses the same scheduling algorithm.
"use_hierarchy" interface is now added to switch between hierarchical mode
and flat mode. For this time being, this interface only appears in Root Cgroup.
V1 -> V2 Changes:
- Raname "struct io_sched_entity" to "struct cfq_entity" and don't differentiate
queue_entity and group_entity, just use cfqe instead.
- Give newly added cfqq a small vdisktime jump accord to its ioprio.
- Make flat mode as default CFQ group scheduling mode.
- Introduce "use_hierarchy" interface.
- Update blkio cgroup documents
[PATCH 1/8 v2] cfq-iosched: Introduce cfq_entity for CFQ queue
[PATCH 2/8 v2] cfq-iosched: Introduce cfq_entity for CFQ group
[PATCH 3/8 v2] cfq-iosched: Introduce vdisktime and io weight for CFQ queue
[PATCH 4/8 v2] cfq-iosched: Extract some common code of service tree handling for CFQ queue and CFQ group
[PATCH 5/8 v2] cfq-iosched: Introduce hierarchical scheduling with CFQ queue and group at the same level
[PATCH 6/8] blkio-cgroup: "use_hierarchy" interface without any functionality
[PATCH 7/8] cfq-iosched: Add flat mode and switch between two modes by "use_hierarchy"
[PATCH 8/8] blkio-cgroup: Document for blkio.use_hierarchy.
Benchmarks:
I made use of Vivek's iostest to perform some benchmarks on my box. I tested different workloads, and
didn't see any performance drop comparing to vanilla kernel. The attached files are some performance
numbers on vanilla Kernel, patched kernel with flat mode and patched kernel with hierarchical mode.
[-- Attachment #2: patched-flat.log --]
[-- Type: text/plain, Size: 5424 bytes --]
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=brr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[brr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
brr 1 1 294 692 1101 1526 3613
brr 1 2 176 420 755 1281 2632
brr 1 4 160 323 583 1253 2319
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=brr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[brr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
brr 1 1 380 738 1092 1439 3649
brr 1 2 171 413 733 1242 2559
brr 1 4 188 350 665 1193 2396
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=bsr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[bsr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
bsr 1 1 6856 11480 17644 22647 58627
bsr 1 2 2592 5409 8464 13300 29765
bsr 1 4 2502 4635 7640 12909 27686
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=bsr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[bsr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
bsr 1 1 6913 11643 17843 22909 59308
bsr 1 2 6682 11234 15527 19410 52853
bsr 1 4 5209 10882 15002 18167 49260
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[drr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drr 1 1 298 701 1117 1538 3654
drr 1 2 190 372 731 1244 2537
drr 1 4 147 322 563 1143 2175
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[drr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drr 1 1 370 713 1050 1416 3549
drr 1 2 192 434 755 1265 2646
drr 1 4 157 333 677 1159 2326
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drw iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[drw] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drw 1 1 595 1272 2007 2737 6611
drw 1 2 269 690 1407 1953 4319
drw 1 4 145 396 978 1752 3271
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drw iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[drw] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drw 1 1 604 1310 1827 2778 6519
drw 1 2 287 723 1368 1887 4265
drw 1 4 170 407 979 1575 3131
[-- Attachment #3: patched-hier.log --]
[-- Type: text/plain, Size: 5424 bytes --]
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=brr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[brr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
brr 1 1 287 690 1096 1506 3579
brr 1 2 189 404 800 1283 2676
brr 1 4 141 317 557 1106 2121
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=brr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[brr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
brr 1 1 386 715 1071 1437 3609
brr 1 2 187 401 717 1258 2563
brr 1 4 296 767 1553 32 2648
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=bsr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[bsr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
bsr 1 1 6971 11459 17789 23158 59377
bsr 1 2 2592 5536 8679 13389 30196
bsr 1 4 2194 4635 7820 13984 28633
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=bsr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[bsr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
bsr 1 1 6851 11588 17459 22297 58195
bsr 1 2 6814 11534 16141 20426 54915
bsr 1 4 5118 10741 13994 17661 47514
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[drr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drr 1 1 297 689 1097 1522 3605
drr 1 2 175 426 757 1277 2635
drr 1 4 150 330 604 1100 2184
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[drr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drr 1 1 379 735 1077 1436 3627
drr 1 2 190 404 760 1247 2601
drr 1 4 155 333 692 1044 2224
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drw iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[drw] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drw 1 1 566 1293 2001 2686 6546
drw 1 2 225 662 1233 1902 4022
drw 1 4 147 379 922 1761 3209
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drw iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[drw] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drw 1 1 579 1226 2020 2823 6648
drw 1 2 276 689 1288 2068 4321
drw 1 4 183 399 798 2113 3493
[-- Attachment #4: vanilla.log --]
[-- Type: text/plain, Size: 5424 bytes --]
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=brr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[brr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
brr 1 1 289 684 1098 1508 3579
brr 1 2 178 421 765 1228 2592
brr 1 4 144 301 585 1094 2124
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=brr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[brr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
brr 1 1 375 734 1081 1434 3624
brr 1 2 172 397 700 1201 2470
brr 1 4 154 316 573 1087 2130
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=bsr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[bsr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
bsr 1 1 6818 11510 17820 23239 59387
bsr 1 2 2643 5502 8728 13329 30202
bsr 1 4 2166 4785 7344 12954 27249
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=bsr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[bsr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
bsr 1 1 6979 11629 17782 23064 59454
bsr 1 2 6803 11274 15865 20024 53966
bsr 1 4 5292 10674 14504 17674 48144
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[drr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drr 1 1 298 694 1116 1540 3648
drr 1 2 183 405 721 1197 2506
drr 1 4 151 296 553 1119 2119
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drr iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[drr] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drr 1 1 367 724 1078 1433 3602
drr 1 2 184 418 744 1245 2591
drr 1 4 157 295 562 1122 2136
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drw iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=0 group_idle=8 quantum=8
=========================================================================
AVERAGE[drw] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drw 1 1 582 1271 1948 2754 6555
drw 1 2 277 700 1294 1970 4241
drw 1 4 172 345 928 1585 3030
Host=localhost.localdomain Kernel=2.6.37-rc2-Block-+
GROUPMODE=1 NRGRP=4
DIR=/mnt/iostestmnt/fio DEV=/dev/sdb2
Workload=drw iosched=cfq Filesz=512M bs=32k
group_isolation=1 slice_idle=8 group_idle=8 quantum=8
=========================================================================
AVERAGE[drw] [bw in KB/s]
-------
job Set NR cgrp1 cgrp2 cgrp3 cgrp4 total
--- --- -- -----------------------------------
drw 1 1 586 1296 1888 2739 6509
drw 1 2 294 749 1360 1931 4334
drw 1 4 156 337 814 1806 3113
next prev parent reply other threads:[~2010-12-13 1:43 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <4CDF7BC5.9080803@cn.fujitsu.com>
[not found] ` <4CDF9CD8.8010207@cn.fujitsu.com>
[not found] ` <20101115193352.GB3396@redhat.com>
2010-11-29 2:32 ` [RFC] [PATCH 3/8] cfq-iosched: Introduce vdisktime and io weight for CFQ queue Gui Jianfeng
[not found] ` <4CDF9CE0.3060606@cn.fujitsu.com>
[not found] ` <20101115194855.GC3396@redhat.com>
2010-11-29 2:34 ` [RFC] [PATCH 4/8] cfq-iosched: Get rid of st->active Gui Jianfeng
[not found] ` <4CDF9D06.6070800@cn.fujitsu.com>
[not found] ` <20101115195428.GE3396@redhat.com>
2010-11-29 2:35 ` [RFC] [PATCH 7/8] cfq-iosched: Enable deep hierarchy in CGgroup Gui Jianfeng
[not found] ` <4CDF9D0D.4060806@cn.fujitsu.com>
[not found] ` <20101115204459.GF3396@redhat.com>
2010-11-29 2:42 ` [RFC] [PATCH 8/8] cfq-iosched: Introduce hierarchical scheduling with CFQ queue and group at the same level Gui Jianfeng
2010-11-29 14:31 ` Vivek Goyal
2010-11-30 1:15 ` Gui Jianfeng
[not found] ` <4CDF9CC6.2040106@cn.fujitsu.com>
[not found] ` <20101115165319.GI30792@redhat.com>
[not found] ` <4CE2718C.6010406@kernel.dk>
2010-12-13 1:44 ` Gui Jianfeng [this message]
2010-12-13 13:36 ` [PATCH 0/8 v2] Introduce CFQ group hierarchical scheduling and "use_hierarchy" interface Jens Axboe
2010-12-14 3:30 ` Gui Jianfeng
2010-12-13 14:29 ` Vivek Goyal
2010-12-14 3:06 ` Gui Jianfeng
2010-12-14 3:29 ` Vivek Goyal
[not found] ` <4D01C6AB.9040807@cn.fujitsu.com>
2010-12-13 1:44 ` [PATCH 1/8 v2] cfq-iosched: Introduce cfq_entity for CFQ queue Gui Jianfeng
2010-12-13 15:44 ` Vivek Goyal
2010-12-14 1:30 ` Gui Jianfeng
2010-12-13 1:44 ` [PATCH 2/8 v2] cfq-iosched: Introduce cfq_entity for CFQ group Gui Jianfeng
2010-12-13 16:59 ` Vivek Goyal
2010-12-14 1:33 ` Gui Jianfeng
2010-12-14 1:47 ` Gui Jianfeng
2010-12-13 1:44 ` [PATCH 3/8 v2] cfq-iosched: Introduce vdisktime and io weight for CFQ queue Gui Jianfeng
2010-12-13 16:59 ` Vivek Goyal
2010-12-14 2:41 ` Gui Jianfeng
2010-12-14 2:47 ` Vivek Goyal
2010-12-13 1:44 ` [PATCH 4/8 v2] cfq-iosched: Extract some common code of service tree handling for CFQ queue and CFQ group Gui Jianfeng
2010-12-13 22:11 ` Vivek Goyal
2010-12-13 1:45 ` [PATCH 5/8 v2] cfq-iosched: Introduce hierarchical scheduling with CFQ queue and group at the same level Gui Jianfeng
2010-12-14 3:49 ` Vivek Goyal
2010-12-14 6:09 ` Gui Jianfeng
2010-12-15 7:02 ` Gui Jianfeng
2010-12-15 22:04 ` Vivek Goyal
2010-12-13 1:45 ` [PATCH 6/8] blkio-cgroup: "use_hierarchy" interface without any functionality Gui Jianfeng
2010-12-15 21:26 ` Vivek Goyal
2010-12-16 2:42 ` Gui Jianfeng
2010-12-16 15:44 ` Vivek Goyal
2010-12-17 3:06 ` Gui Jianfeng
2010-12-17 23:03 ` Vivek Goyal
2010-12-13 1:45 ` [PATCH 7/8] cfq-iosched: Add flat mode and switch between two modes by "use_hierarchy" Gui Jianfeng
2010-12-20 19:43 ` Vivek Goyal
2010-12-13 1:45 ` [PATCH 8/8] blkio-cgroup: Document for blkio.use_hierarchy Gui Jianfeng
2010-12-13 15:10 ` Vivek Goyal
2010-12-14 2:52 ` Gui Jianfeng
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