On Fri, Dec 18, 2015 at 9:38 PM, Christoph Biedl <linux-kernel.bfrz@xxxxxxxxxxxxxxxxxx> wrote: > Henk Slager wrote... > >> you need to do some balancing, as I think that the free space is too >> fragmented and the system fails to allocate extra metadata space >> needed for scrub doing writes into metadata. >> >> # btrfs balance start -dusage=<number> >> with number somewhere between 5 and 50; first start with lower number >> and repeat and increase until the 5.17GiB gets closer down to the >> 3.75GiB > > Thanks, that one worked with number 100. Still some ENOSPC errors but > appeareantly good enough to make scrubbing work. > >> The issue is that for for a filesystem of this size (6.5GiB), it would >> have been better to have mixed data/metadata allocation. See help of >> mkfs.btrfs. So maybe you want to recreate the fs like that, otherwise >> you might easily hit this problem again if you don't monitor free >> space / balance regularly. > > Will keep that in mind. Just out of curiousity: Initially, the file > system size was just 4 Gibyte. Is it possible this made things worse? That should not matter. > Oh, and by the way: > > --- a/Documentation/mkfs.btrfs.asciidoc > +++ b/Documentation/mkfs.btrfs.asciidoc > @@ -77,7 +77,7 @@ where the space is reserved for the other block group type, is not available for > allocation and can lead to ENOSPC state. > + > The recommended size for the mixed mode is for filesystems less than 1GiB. The > -soft recommendation is to use it for filesystems smaller than 5GiB. Thie mixed > +soft recommendation is to use it for filesystems smaller than 5GiB. The mixed > mode may lead to degraded performance on larger filesystems, but is otherwise > usable, even on multiple devices. > + > > > Christoph > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" 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-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
