md raid1 resync speed

Solution Unverified - Updated -

Issue

  • Having few large md mirrors on some DB servers. When adding a new leg to the raid1 resync is quite slow. Disks are some fast storage array Volumes.

According to the manual, md uses idle io time for resync, so the real workload is not affected. However setting /sys/block/mdXXX/md/sync_speed_min doesn't accelerate the resync. It stays at about 4-5MiB/sec.

Could you please provide us some insights how idle time is calculated and in which corner-cases sync_speed_min could be ignored.

Environment

  • Red Hat Enterprise Linux (RHEL) 6.5
  • md raid

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.

Current Customers and Partners

Log in for full access

Log In

New to Red Hat?

Learn more about Red Hat subscriptions

Using a Red Hat product through a public cloud?

How to access this content