[IMPALA-5240] Allow configuration of # of disk I/O threads independently for solid-state and spinning disks

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 2.9.0
• Fix Version/s: Impala 2.10.0
• Component/s: Backend
• Labels: ramp-up
• Epic Color: ghx-label-1
• Assignee: Bikramjeet Vig
• Reporter: Tim Armstrong
• Created: 20/Apr/17 23:45
• Updated: 12/Jul/17 15:26
• Resolved: 12/Jul/17 15:26

Description

Currently Impala defaults to 8 threads per SSD and 1 thread per spinning disk. This can be overridden with --num_threads_per_disk, but that sets the thread count independent of disk type. It would be nice to be able to override the two categories separately in anticipation of more exotic configurations with a mix of spinning disks and potentially high-performance SSDs that won't be maxed-out with 8 threads.