Fortunately, from our testing and the reports of other Linux users looking to see this problem corrected, the relatively small vmscan patches that were published do seem to better address the issue. The user-interface (GNOME in our case) still isn't 100% fluid if the system is sustaining an overwhelming amount of disk activity, but it's certainly much better than before and what's even found right now with the Linux 2.6.35 kernel.
For those interested in this problem or want to try out the patches, here are a few more links worth looking at:
- BugZilla Bug #12304 for the Linux kernel: Large I/O operations result in poor interactive performance and high iowait times.
- Here's the work as a single patch that can be applied against the vanilla 2.6.35 kernel.
- There's a patch for addressing this issue in the Linux 2.6.34 kernel within the Zen Kernel tree (it's also in the Zen 2.6.35 tree).
- Our thread on the topic has tons of other user feedback and information being shared. Wu Fengguang and KOSAKI Motohiro may also soon find themselves overloaded with beer from appreciative users.
Let's hope this work lands successfully into the Linux 2.6.36 kernel and many are also hoping it will work its way back into the Linux 2.6.32 stable series and is picked up by other distribution vendors for their older enterprise-targeted kernels.