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LWN.net Weekly Edition for May 23, 2013
An "enum" for Python 3
An unexpected perf feature
LWN.net Weekly Edition for May 16, 2013
A look at the PyPy 2.0 release
Another Linux capabilities hole found
Posted Apr 16, 2009 14:45 UTC (Thu) by bfields (subscriber, #19510)
Posted Apr 16, 2009 14:48 UTC (Thu) by ajb (subscriber, #9694)
Posted Apr 17, 2009 7:44 UTC (Fri) by michaeljt (subscriber, #39183)
Posted Apr 18, 2009 17:05 UTC (Sat) by i3839 (guest, #31386)
Fundamental issue is that programs use system calls to communicate with the outside world, and most of those system calls deal (sometimes indirectly) with files. For a network filesystem client going through the kernel, then to userspace and back again is just a stupid way of doing something relatively simple.
To sum up, network filesystem clients are in-kernel for all the same reasons why normal filesystems are in-kernel. For network fs servers it's a slightly different trade-off.
Ever further off topic :)
Posted Apr 22, 2009 9:20 UTC (Wed) by michaeljt (subscriber, #39183)
Posted Apr 22, 2009 22:57 UTC (Wed) by nix (subscriber, #2304)
There *is* a cache of disk blocks (the buffer cache), but these days it's
used pretty much entirely for metadata (as this doesn't necessarily have a
page in memory devoted to it).
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