On Sun, May 12, 2013 at 08:00:26PM -0700, PINTU KUMAR wrote: > Dear Mel Gorman, > > I have one question about memory compaction. > Kernel version: kernel-3.4 (ARM) > Chipset: Qual-Comm MSM8930 dual-core. > > We wanted to enable CONFIG_COMPACTION for our product with kernel-3.4. > But QC commented that, enabling compaction on their chip-set is causing > performance degradation for some streaming scenarios (from the beginning). > > I wanted to know is this possible always? > We used compaction with exynos processor and did not observe any performance > degradation. >
I suspect one of their drivers are using high-order allocations and hitting compaction as a result. Compaction is not guaranteed to cause overhead but if it's in use then the scanning and copying overhead can cause problems. > Please let me know your comments. > It will be helpful to decide on enabling compaction or not. > Depends on workload and drivers. -- Mel Gorman SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/