A silly bug in io-bm

It wasn’t enough to impact results, but it was enough to cause questioning my results (and sanity).

Part of the IO operation is having N processes write to 1 file. To make this happen correctly, each process has to compute their offset into the file, and start operations from there.

There is a seek involved. Now if I am smart, it won’t be

lseek(file_descriptor,0,SEEK_SET);

Nope … that would be wrong (the zero).

Having the line like this would mean that 128 GB sized files … might not look like 256 GB sized files.

[root@jr5 ~]# ls -alF /data/file
-rwx------ 1 root root 274877906944 Jul 21 20:43 /data/file*

grrrr….

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