On Wed, 17 Jul 2024 16:20:04 +0530 Bharata B Rao <bharata@xxxxxxx> > On 17-Jul-24 3:07 PM, Vlastimil Babka wrote: > > > > It seems weird to me to see anything that would require ZONE_DMA allocation > > on a modern system. Do you know where it comes from? > > We measured the lruvec spinlock start, end and hold > time(htime) using sched_clock(), along with a BUG() if the hold time was > more than 10s. The below case shows that lruvec spin lock was held for ~25s. > What is more unusual could be observed perhaps with your hardware config but with 386MiB RAM assigned to each node, the so called tight memory but not extremely tight.
