[Pvfs2-users] File affinity and CPU resource scheduling concernswhen using compute node as a PVFS server

[Phil Carns]

Hi,

The cp command line tool is likely using much smaller access sizes than
pvfs2-cp to transfer data.  You can confirm by running cp in strace to
look at what sizes the read() or write() operations are.  In pvfs2-cp
you can toggle the access size with the -b option.

-Phil

л³¤²Å wrote:
> Hi dear Rob:
> I use two I/O data servers, one of them acts as metadata server,
> when i run pvfs2-cp /mnt/pvfs2/abc.ts ~/
> the read speed can reach 11MBytes/s
> but when i mount the pvfs2 system to /mnt/pvfs2 entry
> and then run cp abc.ts ~/ the speed only can reach 4Mbytes/s .
> how can i solve this problem ???
> i know it's slower ,but why only reach 50 persent .