# Consistently limited I/O bandwidth out of Percona Server 8.0

**URL:** <https://forums.percona.com/t/consistently-limited-i-o-bandwidth-out-of-percona-server-8-0/7076>\
**Category:** Other MySQL® Questions\
**Created:** [June 24, 2019, 2:15am UTC](https://forums.percona.com/t/consistently-limited-i-o-bandwidth-out-of-percona-server-8-0/7076 "2019-06-24T02:15:30Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kanwu](https://avatars.discourse-cdn.com/v4/letter/k/ce7236/32.png) [@kanwu](https://forums.percona.com/u/kanwu)\
**Post date:** [June 24, 2019, 2:15am UTC](https://forums.percona.com/t/consistently-limited-i-o-bandwidth-out-of-percona-server-8-0/7076/1 "2019-06-24T02:15:30Z")

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Hi there,

When running Percona Server for MySQL 8.0 with TPC-C workloads on Linux, we consistently seeing very limited I/O (40MB/s read, 40MB/s write) out of Percona Server. Could someone help with this issue? thanks.

1. specifically, our configuration is:  
skip\_name\_resolve  
table\_open\_cache = 200000  
table\_open\_cache\_instances=64  
back\_log=3500  
max\_connections = 4000

innodb\_log\_file\_size=10G # different: 512MB

innodb\_buffer\_pool\_size = 1G # different 512M  
innodb\_log\_buffer\_size=64M # different

innodb\_flush\_method=O\_DIRECT\_NO\_FSYNC #different: fsync  
innodb\_adaptive\_flushing = 0 # same  
innodb\_flush\_neighbors = 0 # same

max\_prepared\_stmt\_count=1000000 # different: 16382

innodb\_doublewrite=ON # undo log: default ON, open  
server\_id=master-01  
log\_bin

1. the problem we saw: there is consistent low IO bandwidth out of Percona Server (40MB/s read, 40MB/s write); which is far from the limit of the disk.

Could someone provide suggestions on this? thanks

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<div class="post-metadata">

**Author:** ![Woll-E](https://avatars.discourse-cdn.com/v4/letter/w/8e7dd6/32.png) [@Woll-E](https://forums.percona.com/u/Woll-E)\
**Post date:** [July 31, 2019, 4:31am UTC](https://forums.percona.com/t/consistently-limited-i-o-bandwidth-out-of-percona-server-8-0/7076/2 "2019-07-31T04:31:15Z")

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Hi kanwum,

Try to add the following values:

innodb\_io\_capacity = 15000  
innodb\_io\_capacity\_max = 30000

Depends on your system, though. This should speed up things a little bit.