[Swift-devel] Avoid copy of local files to work directory?

[Ben Clifford]

On Thu, 23 Apr 2009, Gabri Turcu wrote:

> http://people.cs.uchicago.edu/~gabri/concurrent_mapper/ and

I looked at 
http://people.cs.uchicago.edu/~gabri/concurrent_mapper/report-count-20090422-1853-c819lhq7/karajan.html 
and it doesn't look like the file transfer stuff is using up a large 
portion of time.

The graphs in the karjan tab "karajan FILE_TRANSFER tasks" show most of 
the time no file transfer are happening. If that stagein/stageout step was 
taking a lot of time, then I would expect that to be a solid red block 
showing that the file transfer throttle was being reached often.

Similarly on the info tab, the graph 'how wrapper.sh is spending its time'
and manual observation of a few randomly chosen info files shows that 
hardly any time is being used on input file management compared to 
execution time.

It has been suggested that there is a problem with input file staging 
taking too long, but the above log file seems to suggest that this is not 
at all a problem.

Please can you (plural - whoever it is that thinks file staging is a 
problem here) present some specific evidence to convince me?

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