[IMPALA-10036] Admission control incorrectly rejecting query based on coordinator limit

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 4.0.0
• Fix Version/s: Impala 4.0.0
• Component/s: Backend
• Epic Color: ghx-label-5
• Assignee: Tim Armstrong
• Reporter: David Rorke
• Created: 01/Aug/20 01:02
• Updated: 03/Aug/20 04:34
• Resolved: 03/Aug/20 04:34

Description

Admission control rejected a query with the following error:

ERROR: Rejected query from pool root.default: request memory needed 50.00 GB is greater than memory available for admission 45.36 GB of coordinator-0:22050.

The query profile shows the following resource estimates:

Per-Host Resource Estimates: Memory=303.36GB
Dedicated Coordinator Resource Estimate: Memory=136MB

The max query memory limit for the pool was configured as 50 GB.

Based on the coordinator resource estimate of 136 MB the query should have easily fit in the available coordinator memory. tarmstrong speculated that we might simply be comparing the wrong resource estimate to the coordinator limit.

Profile attached.