PAM: Can not download session log file which name is "DownloadLogServlet"

Products

• CA Privileged Access Manager (PAM)

Issue/Introduction

The session log is downloading and purging manually intermittently.

When you tried to download the session log, the file name is "DownloadLogServlet".
And then, the file's size is 0 bytes after downloaded.

The number of session log record is 249,648.  It seems to be huge.  But it can download if the record size is more than this day.

Success:

2023/04/11 : 251208 records to export  -> logexport20230411043150.csv 100 MB (105,875,599 bytes) 
2023/04/12 : 252644 records to export -> logexport20230412020501.csv 101 MB (106,433,020 bytes)

System Info:

Memory: 16 GB
HDD: 80GB (23% used)

Environment

Release: PAM 4.0.x or later

Cause

The following error occurred in the internal PAM's log:

[Day-Mon-Year hh:mm:ss UTC] PHP Warning:  mysqli_query(): (HY001/1038): Out of sort memory, consider increasing server sort buffer size in ...

It shows a shortage of memory for working sort buffer.
The memory size is defined by the memory on the virtual machine.
In this environment, system memory is only 16 GB.
So, this problem is caused by not having enough memory for sorting session logs. 

 Memory Management

Resolution

To fix the problem, please try each of the following actions.

• manual purge to decrease records in the session log.
• configure auto purge 
• increase memory to 64GB