2012/2/8 Michal Nazarewicz <mina86@xxxxxxxxxx>: > On Wed, 08 Feb 2012 03:04:18 +0100, sandeep patil <psandeep.s@xxxxxxxxx> > wrote: >> >> There's another problem I am facing with zone watermarks and CMA. >> >> Test details: >> Memory : 480 MB of total memory, 128 MB CMA region >> Test case : around 600 MB of file transfer over USB RNDIS onto target >> System Load : ftpd with console running on target. >> No one is doing CMA allocations except for the DMA allocations done by the >> drivers. >> >> Result : After about 300MB transfer, I start getting GFP_ATOMIC >> allocation failures. This only happens if CMA region is reserved. >> Total memory available is way above the zone watermarks. So, we ended >> up starving >> UNMOVABLE/RECLAIMABLE atomic allocations that cannot fallback on CMA >> region. > > > This looks like something Mel warned me about. I don't really have a good > solution for that yet. ;/ What if we have NR_FREE_CMA_PAGES in vmstat and use them to calculate __zone_watermark_ok()? However, it still doesn't solve the problem when we DON'T want to use NR_FREE_CMA_PAGES in case of MOVABLE allocations. Sandeep -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
