Raphael Raph Carvalho

It seems that XFS is smart nowadays to reclaim the wasted disk space on truncate(). This is a 244M generated by Scylla: ``` $ xfs_bmap -vvp ~/tmp/1/keyspace4/standard1-e7445bc0b29911eca2e3e884db8b5af7/me-15-big-Data.db /home/raphaelsc/tmp/1/keyspace4/standard1-e7445bc0b29911eca2e3e884db8b5af7/me-15-big-Data.db: EXT: FILE-OFFSET...

That's confirmed by Brian Foster: ``` > Is ftruncate() sufficient to release extents past-the-end, or do we need an > extra FALLOC_FL_PUNCH_HOLE? Yes, a truncate trims post-eof blocks. ```

> Any idea when this was fixed? @avikivity Checked out to Linux 4.0, and we have xfs_setttr_size() doing: ``` if (newsize

I think it's better for us to decide this than the regular user. Advanced users which are more aware of OS internals (how much memory per CPU it needs?) is...

@mariusgrigaitis some systems don't allow a non-root program to read /proc/kallsyms, which meltdown-checker is built upon. Without it, we can't easily check if system is still affected by meltdown. Worth...

@mariusgrigaitis i'll update the program to print an informative msg for this scenario. thanks for reporting it. i'll see what i can do to fix this issue.

@mariusgrigaitis could you please inform what's the output of 'cat /proc/kallsyms | grep sys_call_table'?

@mariusgrigaitis that's awkward, no sys_call_table. What's your kernel version? Could u pls try the same with /boot/System.map*? If it does work on /boot/System.map*, I'll make the checker fallback on it.

@mariusgrigaitis ed5c4b20523fe6b27f66f26f3b0fd77f73c2fffc may help you. pull the latest changes and try again with root.

@dlenski interesting. i added code for user to be aware of it here: https://github.com/raphaelsc/Am-I-affected-by-Meltdown/blob/master/meltdown_checker.cc#L172 I'm currently looking for alternatives to remove the need for root in such systems, like creating...