Hi, Michal, Michal Hocko <mhocko@xxxxxxxxxx> writes: > On Wed 27-09-17 23:10:08, Minchan Kim wrote: >> On Wed, Sep 27, 2017 at 03:50:34PM +0200, Michal Hocko wrote: >> > On Wed 27-09-17 22:41:17, Minchan Kim wrote: >> > > On Wed, Sep 27, 2017 at 03:22:41PM +0200, Michal Hocko wrote: >> > [...] >> > > > simply cannot disable swap readahead when page-cluster is 0? >> > > >> > > That's was what I want really but Huang want to use two readahead >> > > algorithms in parallel so he wanted to keep two separated disable >> > > knobs. >> > >> > If it breaks existing and documented behavior then it is a clear >> > regression and it should be fixed. I do not see why this should be >> > disputable at all. >> >> Indeed but Huang doesn't think so. He has thought it's not a regression. >> Frankly speaking, I'm really bored of discussing with it. >> https://marc.info/?l=linux-mm&m=150526413319763&w=2 > > Then send a patch explaining why you consider this a regression with > some numbers backing it and I will happily ack it. I still think there may be a performance regression for some users because of the change of the algorithm and the knobs, and the performance regression can be resolved via setting the new knob. But I don't think there will be a functionality regression. Do you agree? Best Regards, Huang, Ying >> So I passed the decision to Andrew. >> http://lkml.kernel.org/r/<20170913014019.GB29422@bbox> >> >> The config option idea is compromise approach although I don't like it >> and still believe it's simple clear *regression* so 0 page-cluster >> should keep the swap readahead disabled. > > It is not a compromise. The regression is still there for many users > potentially (just consider zram distribution kernel users...). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
