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From: Ivan Voras <ivoras@fer.hr>
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Subject: Re: NFS write() calls lead to read() calls?
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Ulrich Spoerlein wrote:

> What kind of C program or script did you have in mind? My C-foo is very=
=20
> weak ...

If you have python installed, this is a simple way:

----
print "writing"
f =3D file("a_file", "w")
for x in xrange(1024): # write 1024 MB
     f.write(' '*1024*1024)
f.close()

raw_input("press enter to rewrite")

print "rewriting"
f =3D file("a_file", "r+")
for x in xrange(1024): # write 1024 MB again
     f.write(' '*1024*1024)
f.close()
----

save it to a file, run the file with python interpreter. If you don't=20
observe the weird read-before-write effect, then it's not a problem in=20
FreeBSD / NFS.


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