Query Error: "Cannot Open more than 262144 Append-only table Segment files Concurrently (appendonlywriter.c:1150)"

Products

• Services Suite

Issue/Introduction

Symptoms:

External table query is failing with the following error message:

ERROR: cannot open more than 262144 append-only table segment files cocurrently (appendonlywriter.c:464)

Environment

Cause

The threshold of max_appendonly_segfiles has been reached.

Resolution

There are two ways of fixing this issue and it will depend on how changes are normally made in the cluster.

If changes are normally made through Ambari (recommended), increase the max_appendonly_segfiles via Ambari:

1. Click on HAWQ in the left pane

2. Click on Configs

3. Click on Advanced

4. Click on Custom Hawq-site

5. Then add the configuration "max_appendonly_segfiles" = "400000" (The default value is 262144).

OR

If changes are made through CLI: (WARNING: If changes or restarts are subsequently done via Ambari, these changes will be overwritten):

1. Hawq config -s max_appendonly_segfiles (This will show you the current value).

2. Hawq config -c max_appendonly_segfiles -v 400000 (This will change the value to 400000).

Please set the value that works best for your environment. The value of 400000 was only used as an example.