On Sun, Feb 7, 2016 at 9:49 PM, Kouhei Kaigai <kai...@ak.jp.nec.com> wrote: > On the other hands, it also became clear we have to guarantee OS buffer > or storage block must not be updated partially during the P2P DMA. > My motivation is a potential utilization of P2P DMA of SSD-to-GPU to > filter out unnecessary rows and columns prior to loading to CPU/RAM. > It needs to ensure PostgreSQL does not write out buffers to OS buffers > to avoid unexpected data corruption. > > What I want to achieve is suspend of buffer write towards a particular > (relnode, forknum, blocknum) pair for a short time, by completion of > data processing by GPU (or other external devices). > In addition, it is preferable being workable regardless of the choice > of storage manager, even if we may have multiple options on top of the > pluggable smgr in the future.
It seems like you just need to take an exclusive content lock on the buffer, or maybe a shared content lock would be sufficient. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
