Environment
Retain 4.0.3
Situation
I am migrating indexes after upgrading from Retain 3 to Retain 4. Is there a way to speed up the indexing?
Resolution
There are several factors that affect indexing performance:
- Disk I/O speed
- RAM
- Cores/threads
You could make the following change to increase the indexing threads; however, if you have slower disk I/O or if the system needs more RAM, you may not see any benefit. The are all interrelated.
To increase indexing threads:
- Stop tomcat
- Edit ../RetainServer/WEB-INF/classes/config/solrcloud.indexing.properties
- At the end of the file, change the setting: indexingThreads=0 to indexingThreads=[1 - 24]
- Start tomcat
You should not go higher than 10 - 20 times the CPU cores; otherwise, the overhead of CPU slicing would actually work against you.
You will also need to keep in account users needing to access their Retain mailboxes and perform searches. Increasing threads could slow down the web UI response, so you'll need to experiment with what works best for your system.
Right now, there is a limit of 24 threads. We are considering removing that limit; but, at the time of this article, that has not been decided.
Additional Information
This article was originally published in the GWAVA knowledgebase as article ID 2828.