Vdbench, Linux, and openflags=x_SYNC

It was just brought to my attention that there are some problems with the way that I implemented the O_SYNC, O_DSYNC, and O_RSYNC flags for Linux.

First of all, I misinterpreted what I found in /usr/include/bits/fcntl.h The flags are octal, not hex as I mistakenly read, meaning that what I coded as 0x010000 should have been 0x1000.

Second, I learned that the flags themselves have changed since I last looked at it, with the three flags in some versions of Linux no longer having the same value (octal 010000), but instead now have different values.

Since I can't begin to identify and check all the different flavors and versions of Linux and their flag settings I highly suggest before using these flags to check the contents of above header file and code openflags=0x…… with the proper HEX value as needed.

The next 503rcx version will have the 'proper' flags set to 0x1000, (whatever 'proper' means today).

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Blog for Henk Vandenbergh, author of Vdbench, and Sun StorageTek Workload Analysis Tool (Swat). This blog is used to keep you up to date about anything revolving around Swat and Vdbench.

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