From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andreas Rohner Subject: Re: [PATCH 1/4] nilfs-utils: cldconfig add an option to set minimal free blocks Date: Mon, 20 Jan 2014 11:52:27 +0100 Message-ID: <52DCFFEB.4070809@gmx.net> References: <685e5c720189d1e451ed8a0d65581aa8c5a3f7f0.1390139797.git.andreas.rohner@gmx.net> <1390212899.3034.66.camel@slavad-ubuntu> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1390212899.3034.66.camel@slavad-ubuntu> Sender: linux-nilfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: slava-yeENwD64cLxBDgjK7y7TUQ@public.gmane.org Cc: linux-nilfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Hi Vyacheslav, On 2014-01-20 11:14, Vyacheslav Dubeyko wrote: > On Sun, 2014-01-19 at 15:01 +0100, Andreas Rohner wrote: > > It is expected "From: " and "Subject: " > in the begin of patch. Are you sure? I don't see that in other patches and I think this information is already contained in the email headers. I used "git send-email" to submit the patch. >> With this option the user can specify the minimal number of free/dead >> blocks, which is a threshold for the GC. If there are less free blocks >> to gain from cleaning a segment than the specified number, the GC will >> abort and try again with a different segment. >> > > What will be under stress? I mean situation when we processed all > segments that it is valuable for cleaning on threshold basis. Then we > need to clean segments for space allocation but all "dirty" segments not > reasonable choice for cleaning because of threshold. You have a point here. I could add another option that is used when the file system is under stress. Just like with cleaning_interval and mc_cleaning_interval. By setting the mc-option to 0 you could disable the threshold under stress. > What will we have in situation when an user selects not proper value of > threshold? Well that's the users problem. You could also ask what will happen if the user selects an improper min_clean_segments value ;) > I worried about situation of skipping sibling segments from cleaning. Is > NILFS2 driver really ready for this? Did you think about efficiency of > free space allocation after such cleaning and about file system > consistency? Are you sure that all will be good after such approach of > cleaning? I simply want to be sure that you have analyzed this. I tested it extensively and I am quite sure, that there are no problems with that on the driver side. Thanks for reviewing my patches, Best regards, Andreas Rohner -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html