> I have a an OSC caching question. I am running a dd process > which writes an 8GB file. The file is on lustre, striped > 8x1M.
How the Lustre instance servers store the data may not have a huge influence on what happens in the client's system buffer cache. > This is run on a system that has 2 NUMA nodes ( cpu sockets). > [...] Why does lustre go to the trouble of dumping node1 and > then not use node1's memory, when there was always plenty of > free memory on node0? What makes you think "lustre" is doing that? Are you aware of the values of the flusher settings such as 'dirty_bytes', 'dirty_ratio', 'dirty_expire_centisecs'? Have you considered looking at NUMA policies e.g. as described in 'man numactl'? Also while you surely know better I usually try to avoid buffering large amounts of to-be-written data in RAM (whether on the OSC or the OSS), and to my taste 8GiB "in-flight" is large. _______________________________________________ lustre-discuss mailing list [email protected] http://lists.lustre.org/listinfo.cgi/lustre-discuss-lustre.org
