Zheng Da wrote:
I create a file of 4GB in XFS (the ramdisk has 5GB of space). My test program overwrites 4G of data to the file
---- It sounds like you are asking why multiple threads don't move memory from one point to another point in memory at a faster rate than one thread alone. I.e. if you had 2 processes doing an assembly instruction, memmov to move a chunk of memory from 1 area to another, would you expect to do the move any faster if you had 2 processors doing the move vs. 1?? I think the limiting factor (unless you have a slow processor and some REALLY fast memory, but stock x86-64 parts, today have memory running about 2-4 times slower than the processor -- so the memory is usually the bottleneck. Two processes wouldn't do it any faster, and might actually do it slower due to resource contention issues -- I would *think*... but I really don't know the details of how writing from mem2mem and having the target be in the format of and xfs file system, would cause cpu-bound delays that would be significant to change the fact that m2m operations are usually mem-bandwidth limited...? (I don't know the answers, just clarifying what you are asking)... _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
