Many cachegrind.out.xxxxxx were generated in /private/var/tmp and disk space filled up

Recently I found that the free disk space of my Mac OS X (Yosemite) got very small, so I looked into why.

$ sudo du -sh /*

$ sudo du -sh /private/*

$ sudo du -sh /private/var/*

Finally I found that /private/var/tmp contained over 200GB files.
In /private/var/tmp there are many files whose name are such as cachegrind.out.50526.
It is said that these files are generated by Xdebug profiler.
Yes, I use Xdebug from MacPorts.
Xdebug is convenient because it shows stacktrace in error, enables stepping execution (but it needs Eclipse...), and so on.

Then I attempted to delete them with rm but an error occurred.

$ sudo rm cachegrind.out.*
-bash: sudo: Argument list too long

Because the files were too many, shell expansion for "*" caused Argument list too long error.

Therefore I deleted them using find -exec.

$ cd /private/var/tmp
$ sudo find . -name 'cachegrind.out.*' -maxdepth 1 -exec rm {} \;

I got about 200GB free space.

See below for details about find -exec.
Delete or grep the results of find

If this goes on, files will be generated and they will fill up my disk again. So I decided to modify Xdebug setting so that Xdebug profiler will generate output files not in /private/var/tmp but in /tmp directory.
(I also set trace output directory to /tmp)
They will be deleted on rebooting.

Add xdebug.profiler_output_dir and xdebug.trace_output_dir.

xdebug.profiler_output_dir=/tmp/ ; where the profiler output will be written to
xdebug.trace_output_dir=/tmp/ ; where the tracing files will be written to

Xdebug: Documentation.