Hi,
Acting on a tip-off I measured the transfer rate from one of the Canadaian
clusters to cern. I discovered that
globus-url-copy -tcp-bs 16777216 ....
is about 25 times faster than with the default buffer size, 2.5MB/s
comapared to 100kB/s.
Is this indicative of some bad network setting, routing, ..., or is this
to be expected for transatlantic transfers - I mean the size of the
improvement.
How do I make the LCG utils (lcg-cp) use a larger buffer size?
I found some optimizations from SC2/3
net.ipv4.tcp_rmem = 1048576 16777216 33554432
net.ipv4.tcp_wmem = 1048576 16777216 33554432
net.ipv4.tcp_mem = 1048576 16777216 33554432
net.core.rmem_max = 16777215
net.core.wmem_max = 16777215
net.core.rmem_default = 4194303
net.core.wmem_default = 4194303
Will these mean that globus-url-copy will no longer need the tcp-bs
argument?
Cheers,
Rod.
--
Rod Walker +1 6042913051
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