SSD VS HDD 在INNODB 上的性能比较

由于项目后端存储的需要，需要高性能的存储设备。特此比较Fusion IO （80G）和 RAID5 的mysql性能,采用sysbench v0.4.8 来测试

//innodb中创建100k条数据
./sysbench --test=oltp --mysql-table-engine=innodb --oltp-table-size=1000000 --mysql-socket=/tmp/mysql1.sock prepare --mysql-user=terry --mysql-password=terry
mysql> show table status;
+--------+--------+---------+------------+---------+----------------+-------------+-----------------+--------------+------------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+---------+
| Name   | Engine | Version | Row_format | Rows    | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free  | Auto_increment | Create_time         | Update_time | Check_time | Collation       | Checksum | Create_options | Comment |
+--------+--------+---------+------------+---------+----------------+-------------+-----------------+--------------+------------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+---------+
| sbtest | InnoDB |      10 | Compact    | 1000109 |            225 |   225132544 |               0 |     18399232 | 8584691712 |        1000001 | 2011-03-16 10:43:28 | NULL        | NULL       | utf8_general_ci |     NULL |                |         |
+--------+--------+---------+------------+---------+----------------+-------------+-----------------+--------------+------------+----------------+---------------------+-------------+------------+-----------------+----------+----------------+---------+

第一次测试，innodb buffer 开的比较高 数据基本上都缓存住了

SSD

OLTP test statistics:
queries performed:
read:                            1400028
write:                           500010
other:                           200004
total:                           2100042
transactions:                        100002 (2271.75 per sec.)
deadlocks:                           0      (0.00 per sec.)
read/write requests:                 1900038 (43163.33 per sec.)
other operations:                    200004 (4543.51 per sec.)
Test execution summary:
total time:                          44.0197s
total number of events:              100002
total time taken by event execution: 703.3672
per-request statistics:
min:                            0.0023s
avg:                            0.0070s
max:                            0.6603s
approx.  95 percentile:         0.0176s
Threads fairness:
events (avg/stddev):           6250.1250/55.38
execution time (avg/stddev):   43.9604/0.00

HDD

./sysbench --num-threads=16 --max-requests=100000 --test=oltp --oltp-table-size=1000000 --mysql-socket=/tmp/mysql1.sock  --mysql-user=terry --mysql-password=terry run
sysbench v0.4.8:  multi-threaded system evaluation benchmark
OLTP test statistics:
queries performed:
read:                            1400056
write:                           500020
other:                           200008
total:                           2100084
transactions:                        100004 (2324.85 per sec.)
deadlocks:                           0      (0.00 per sec.)
read/write requests:                 1900076 (44172.19 per sec.)
other operations:                    200008 (4649.70 per sec.)
Test execution summary:
total time:                          43.0152s
total number of events:              100004
total time taken by event execution: 686.9507
per-request statistics:
min:                            0.0024s
avg:                            0.0069s
max:                            0.5917s
approx.  95 percentile:         0.0223s
Threads fairness:
events (avg/stddev):           6250.2500/70.82
execution time (avg/stddev):   42.9344/0.01

性能基本上差不都 ，都被cache住了。

07:30:01 AM     CPU     %user     %nice   %system   %iowait    %steal     %idle
09:10:01 AM     all      0.03      0.00      8.69      0.00      0.00     91.28
09:20:01 AM     all      0.03      0.00      8.38      0.00      0.00     91.60
09:30:01 AM     all      0.03      0.00      8.44      0.00      0.00     91.53
09:40:01 AM     all      0.03      0.00      8.39      0.00      0.00     91.58
09:50:01 AM     all      0.03      0.00      8.50      0.00      0.00     91.48
10:00:01 AM     all      0.03      0.00      8.72      0.00      0.00     91.25

没有iowait , CPU使用了1-2个核。

第二次测试，innodb buffer 开的很低（1k） 数据走direct_IO方式写入底层存储（innodb_flush_method=O_DIRECT）

SSD

OLTP test statistics:
queries performed:
read:                            1400014
write:                           500005
other:                           200002
total:                           2100021
transactions:                        100001 (63.42 per sec.)
deadlocks:                           0      (0.00 per sec.)
read/write requests:                 1900019 (1204.98 per sec.)
other operations:                    200002 (126.84 per sec.)
Test execution summary:
total time:                          1576.8096s
total number of events:              100001
total time taken by event execution: 25227.3666
per-request statistics:
min:                            0.0137s
avg:                            0.2523s
max:                            2.3590s
approx.  95 percentile:         0.6610s
Threads fairness:
events (avg/stddev):           6250.0625/31.85
execution time (avg/stddev):   1576.7104/0.03

测试期间的 SAR 数据
07:30:01 AM     CPU     %user     %nice   %system   %iowait    %steal     %idle
10:50:01 AM     all      9.23      0.00     10.09      0.07      0.00     80.60
11:00:01 AM     all      1.85      0.00      9.29      1.94      0.00     86.92
11:10:01 AM     all      9.03      0.00     12.64      9.70      0.00     68.63
11:20:01 AM     all      8.73      0.00     12.34      9.66      0.00     69.27
11:30:01 AM     all      3.46      0.00     10.10      3.80      0.00     82.65
Average:        all      0.50      0.00      8.67      0.37      0.00     90.46

IOWAIT 比较高

HDD

OLTP test statistics:
queries performed:
read:                            1400014
write:                           500005
other:                           200002
total:                           2100021
transactions:                        100001 (38.86 per sec.)
deadlocks:                           0      (0.00 per sec.)
read/write requests:                 1900019 (738.26 per sec.)
other operations:                    200002 (77.71 per sec.)
Test execution summary:
total time:                          2573.6523s
total number of events:              100001
total time taken by event execution: 41169.6306
per-request statistics:
min:                            0.0114s
avg:                            0.4117s
max:                            1.7586s
approx.  95 percentile:         0.7781s
Threads fairness:
events (avg/stddev):           6250.0625/27.99
execution time (avg/stddev):   2573.1019/0.15

07:30:01 AM       CPU     %user     %nice   %system   %iowait    %steal     %idle
11:00:01 AM       all      1.57      0.00      0.75      7.46      0.00     90.22
11:10:01 AM       all      2.40      0.00      1.14     11.18      0.00     85.28
11:20:01 AM       all      2.46      0.00      1.17     11.81      0.00     84.57
11:30:01 AM       all      2.43      0.00      1.16     12.06      0.00     84.35
Average:          all      0.31      0.00      0.13      0.62      0.00     98.93

IOWAIT 比较高，最高时到达了18%

在这组测试中，HDD的性能比FUSION IO 低了50%左右。可能是由于顺序读写FUSION IO性能没有充分体现出来。