On 08/21/2013 08:22 AM, Jerome Marchand wrote: >> > Instead of introducing yet another tunable, why don't we just make the >> > ratio that comes in from the user more fine-grained? >> > >> > sysctl overcommit_ratio=0.2 >> > >> > We change the internal 'sysctl_overcommit_ratio' to store tenths or >> > hundreths of a percent (or whatever), then parse the input as two >> > integers. I don't think we need fully correct floating point parsing >> > and rounding here, so it shouldn't be too much of a chore. It'd >> > probably end up being less code than you have as it stands. >> > > Now that I think about it, that could break user space. Sure write access > wouldn't be a problem (one can still write a plain integer), but a script > that reads a fractional value when it expects an integer might not be able > to cope with it.
You're right. Something doing FOO=$(cat overcommit_ratio) and then trying do do arithmetic would just fail loudly. But, it would probably fail silently if we create another tunable that all of a sudden returns 0 (when the kernel is not _behaving_ like it is set to 0). I'm not sure there's a good way out of this without breakage (or at least confusing) of _some_ old scripts/programs. Either way has ups and downs. The existing dirty_ratio/bytes stuff just annoys me because I end up having to check two places whenever I go looking for it. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
