# Innodb-buffer-pool-size versus performance **URL:** \ **Category:** Percona Server for MySQL 5.7\ **Created:** [August 22, 2021, 10:12pm UTC](https://forums.percona.com/t/innodb-buffer-pool-size-versus-performance/11874 "2021-08-22T22:12:27Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![artur](https://avatars.discourse-cdn.com/v4/letter/a/53a042/32.png) [@artur](https://forums.percona.com/u/artur)\ **Post date:** [August 22, 2021, 10:12pm UTC](https://forums.percona.com/t/innodb-buffer-pool-size-versus-performance/11874/1 "2021-08-22T22:12:27Z")
Hello, this is my first post so please be understanding. I am trying to configure the size of innodb-buffer-pool-size correctly but I don’t see the difference in the benchmark. My hardware: CPU: Intel Xeon E-2236 (6 core, 12 Threads) Disks: 2 x Micron\_7300\_MTFDHBE1T9TDF, software Raid 1 with mdadm OS: Centos 7 RAM: 32GB Percona 5.7 OS tuning: nothing special: noatime in /etc/fstab, vm.swappiness = 1, tuned profile: throughput-performance SQL system limits ```auto # cat /proc/29065/limits Limit Soft Limit Hard Limit Units Max cpu time unlimited unlimited seconds Max file size unlimited unlimited bytes Max data size unlimited unlimited bytes Max stack size 8388608 unlimited bytes Max core file size 0 unlimited bytes Max resident set unlimited unlimited bytes Max processes 257181 257181 processes Max open files 65536 65536 files Max locked memory unlimited unlimited bytes Max address space unlimited unlimited bytes Max file locks unlimited unlimited locks Max pending signals 257181 257181 signals Max msgqueue size 819200 819200 bytes Max nice priority 0 0 Max realtime priority 0 0 Max realtime timeout unlimited unlimited us ``` Sysbench command: `sysbench oltp_read_only --tables=10 --table-size=1000000 --mysql-socket=/var/lib/mysql/mysql.sock --mysql-db=sbtest --mysql-user=root --mysql-password=xxx --time=300 --threads=12 --report-interval=1 run` Results without any customization in /etc/my.cnf: ```auto mysql> SHOW VARIABLES LIKE 'innodb_buffer_pool_size'; +-------------------------+-----------+ | Variable_name | Value | +-------------------------+-----------+ | innodb_buffer_pool_size | 134217728 | +-------------------------+-----------+ SQL statistics: queries performed: read: 37424674 write: 0 other: 5346382 total: 42771056 transactions: 2673191 (8910.55 per sec.) queries: 42771056 (142568.86 per sec.) ignored errors: 0 (0.00 per sec.) reconnects: 0 (0.00 per sec.) General statistics: total time: 300.0018s total number of events: 2673191 Latency (ms): min: 0.78 avg: 1.35 max: 17.85 95th percentile: 1.39 sum: 3596988.45 Threads fairness: events (avg/stddev): 222765.9167/1429.75 execution time (avg/stddev): 299.7490/0.01 ``` Result with such a configuration file: ```auto [mysqld] datadir = /var/lib/mysql log-error = /var/log/mysqld.log socket = /var/lib/mysql/mysql.sock pid-file = /var/run/mysqld/mysqld.pid innodb-buffer-pool-size = 16G innodb-log-file-size = 4G innodb-flush-method = O_DIRECT ``` ```auto mysql> SHOW VARIABLES LIKE 'innodb_buffer_pool_size'; +-------------------------+-------------+ | Variable_name | Value | +-------------------------+-------------+ | innodb_buffer_pool_size | 17179869184 | +-------------------------+-------------+ SQL statistics: queries performed: read: 37749712 write: 0 other: 5392816 total: 43142528 transactions: 2696408 (8987.94 per sec.) queries: 43142528 (143807.07 per sec.) ignored errors: 0 (0.00 per sec.) reconnects: 0 (0.00 per sec.) General statistics: total time: 300.0018s total number of events: 2696408 Latency (ms): min: 0.70 avg: 1.33 max: 13.08 95th percentile: 1.39 sum: 3596925.29 Threads fairness: events (avg/stddev): 224700.6667/937.97 execution time (avg/stddev): 299.7438/0.00 ``` These results are basically the same. Shouldn’t there be a noticeable performance improvement when increasing innodb-buffer-pool-size? I repeated the tests 5 times and took into account the latest results. Am I doing something wrong? ---
**Author:** ![Ivan\_Groenewold](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/ivan_groenewold/32/6299_2.png) [@Ivan\_Groenewold](https://forums.percona.com/u/Ivan_Groenewold)\ **Post date:** [August 25, 2021, 2:25pm UTC](https://forums.percona.com/t/innodb-buffer-pool-size-versus-performance/11874/2 "2021-08-25T14:25:03Z")
Hi artur, welcome to the forum. It is likely that the dataset is fitting in memory even with the default buffer pool settings. If you run with a bigger dataset that forces the disks to be involved, you should notice the difference. Also there is caching by the OS buffers. You should drop os caches between test runs: echo “3” \> /proc/sys/vm/drop\_caches ---
**Author:** ![artur](https://avatars.discourse-cdn.com/v4/letter/a/53a042/32.png) [@artur](https://forums.percona.com/u/artur)\ **Post date:** [August 26, 2021, 9:11pm UTC](https://forums.percona.com/t/innodb-buffer-pool-size-versus-performance/11874/3 "2021-08-26T21:11:16Z")
Thank you for your reply. The problem was resolved after replacing the memory. Strange because this memory works in a second server without any problems. ```auto SQL statistics: queries performed: read: 67209114 write: 0 other: 9601302 total: 76810416 transactions: 4800651 (16002.04 per sec.) queries: 76810416 (256032.63 per sec.) ignored errors: 0 (0.00 per sec.) reconnects: 0 (0.00 per sec.) General statistics: total time: 300.0019s total number of events: 4800651 Latency (ms): min: 0.92 avg: 1.12 max: 7.31 95th percentile: 1.39 sum: 5396224.98 Threads fairness: events (avg/stddev): 266702.8333/1034.61 execution time (avg/stddev): 299.7903/0.00 ```