Okay. I follow. Basically the cache is so large that the call to fill it starves out memory requests from pretty much everything else. Especially with an extra large cache, because the kernel memory used for the initial read / processing takes lots of memory away from other kernel processes. Shrinking the cache makes the problem less of an issue because there is less to fill and the transfer happens quickly enough and are small enough that the other processes are less likely to get choked out by it.

Nice RAID transfer rate jump, by the way!!! Significantly greater throughput!!! COOL!

Edit: And since it is totally dependent on memory size and kernel, the upgrade to 100GB drives is not the issue, other than the side effect of a larger database. And it was not an issue previously with the 80s because the database size was smaller and I was running under 2.00 / older hijack. The only other test I would be curious about is if this would also happen under 2.00 - to see if the memory enhancements made there changed matters or if it is an inherent problem.