Red Hat Bugzilla – Bug 1295892
rhel6+ ksh regression due to default to mmap for internal malloc
Last modified: 2017-06-13 04:39:39 EDT
Created attachment 1111915 [details]
The example script, when run as:
$ ./kshscript driver
will run around 5 times slower in rhel6+ when compared
to rhel5 version of ksh.
A possible workaround is to run as:
VMALLOC_OPTIONS=break ./kshscript driver
to have the same behavior as rhel5 ksh.
Another solution is to use system malloc, e.g. have
-D_AST_std_malloc=1 in CFLAGS, what will cause it to
make very few mmap calls and run fast as well (but
make VMALLOC_OPTIONS a noop).