On 2014-03-16 14:34, Vyacheslav Dubeyko wrote: > >> On 16 марта 2014 г., at 16:24, Andreas Rohner <andreas.rohner@xxxxxxx> wrote: >> >>> On 2014-03-16 14:00, Vyacheslav Dubeyko wrote: >>> >>>> On Mar 16, 2014, at 1:47 PM, Andreas Rohner wrote: >>>> >>>> This patch adds an additional timestamp to the segment usage >>>> information that indicates the last time the usage information was >>>> changed. So su_lastmod indicates the last time the segment itself was >>>> modified and su_lastdec indicates the last time the usage information >>>> itself was changed. >>> >>> What will we have if user changes time? >>> What sequence will we have after such "malicious" action? >>> Did you test such situation? >> >> The timestamp is just a hint for the userspace GC. If the hint is wrong >> the result would be that the GC is less efficient for a while. After a >> while it would go back to normal. You have the same problem with the >> already existing su_lastmod timestamp. >> > > But I worry about such thing. Previously, we had complains of users about > different issues with timestamp policy of GC. And I had hope that namely > new GC policies can resolve such GC disadvantage. So, what have we again? > The same issue of GC? Yes but I have to compare it to the protection period, which is a timestamp. Maybe I could use the current checkpoint number instead... Regards, Andreas Rohner > Thanks, > Vyacheslav Dubeyko. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
