Advice on Indexing

[Greg Roodt]

I have a MySQL database server running version 5.0.77. The server load persistently borders on maximum resource usage. I also have a master slave configuration for purpose of replication.

One of the very active tables is 3.5 Gb in size. There are several indexes defined and I need to add a new index. The last time I tried adding an index the load peaked and stayed maximum for about 5+ hours, although the table was substantially bigger at the time and replication was not active.

I am not sure if this time frame to add an index is an acceptable average or excessive. Given the current configuration and load situation I am loathe to simply add another index and was hoping someone had some experience with this and could tell me what to expect and any precautions I should take before adding the index.


I also need to know if there will be any implications regards the replication etc. server during this excercise?