-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hi Konstantin,
On Mon, 2016-07-25 at 19:06 +0300, Konstantin Khomoutov wrote: > > mergerfs is a union filesystem geared towards simplifing storage > > I supposed it should be "simplifying" in both cases. > THanks. Corrected in my packaging. > > and management of files across numerous commodity storage devices. It > > is similar to mhddfs, unionfs, and aufs. > > > > Some salient features include > > * Runs in userspace (FUSE) > > * Configurable behaviors > > * Support for extended attributes (xattrs) > > * Support for file attributes (chattr) > > * Runtime configurable (via xattrs) > > * Safe to run as root > > * Opportunistic credential caching > > * Works with heterogeneous filesystem types > > * Handling of writes to full drives > > What does this mean? Drives with no more room to write data left? mergefs allows union mount, created out of multiple drives. Take this example tmpfs -> /tmp-ram - 4G /dev/sdb2 -> /tmp-disk - 10G mergerfs can help create a unified mount: /tmp-ram:/tmp-disk /tmp mergerfs So, for a 5 GiB file, mergerfs would intelligently write it to the block based backing device. Here are some stats: rrs@learner:~$ df -h /tmp Filesystem Size Used Avail Use% Mounted on tmp-ram:media/SSHD/tmp-disk:tmp-disk 483G 415G 64G 87% /tmp 2016-07-25 / 22:25:24 ♒♒♒ ☺ rrs@learner:~$ for x in 1 2 3 4 5 6 7 8 9; do dd if=/dev/zero of=/tmp/$x.img bs=1M count=500; done 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 2.55788 s, 205 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 1.6153 s, 325 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 8.25114 s, 63.5 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 1.84161 s, 285 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 2.11159 s, 248 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 14.8864 s, 35.2 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 1.77783 s, 295 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 1.74245 s, 301 MB/s 500+0 records in 500+0 records out 524288000 bytes (524 MB, 500 MiB) copied, 14.1321 s, 37.1 MB/s 2016-07-25 / 22:26:57 ♒♒♒ ☺ The actual data is internally moved to the optimal backing device, based on policies explained in the following link, under section POLICIES https://github.com/trapexit/mergerfs rrs@learner:~$ ls /tmp 1.img 2.img 3.img 4.img 5.img 6.img 7.img 8.img 9.img .....snipped..... 2016-07-25 / 22:28:25 ♒♒♒ ☺ rrs@learner:~$ ls /media/SSHD/tmp-disk/ 1.img 9.img 2.img 3.img 4.img 5.img 6.img 7.img 8.img .....snipped..... 2016-07-25 / 22:28:33 ♒♒♒ ☺ rrs@learner:~$ ls /tmp-ram/ 2016-07-25 / 22:28:43 ♒♒♒ ☺ We get good throughput and at the same time efficiency. This is just one of the many use cases. - -- Ritesh Raj Sarraf | http://people.debian.org/~rrs Debian - The Universal Operating System -----BEGIN PGP SIGNATURE----- iQIcBAEBCgAGBQJXlkZWAAoJEKY6WKPy4XVpe0YQALgKImgpU3OM3z51JjvLRu5a bWKlspcMC1AhPmvvlHlyHUjkPIzWsJKsOexlslwwExjW6S6TTXoeHfEkfp8Xua23 aC1N1xbI6tvB6pEAfnijSA85SQ0QguMxmRNrXmDVJ6LyXTaU3yewaWIrjkXoJw8R E/RKssxTwPKvAc5fd1hmcMWxBKEL+kJO1JmrDmbNdgWn01rseSghnd0cr+A1HVuE YebysE5qkvjet2lruqR80jVXH6DJJnzl6cBI5Te1+dksk9BHCkuz0IP2lbM1Z7Bq e520E5S2Tx6A+Knmtssg3G48zYWhw0DH78/DyNo+7UTcx8GC1TKKKW/tQgDdm77H jBzpucnF4jb8Ike67czdEYif76sC6xne+IUWHCuUPJCqVENMOG1TN69qCWrh8F0f 0tK8qR0tM7g9n3A2Tx7BG1J5hVFiMcMONUzfwH+vXPnVip9y3CDvwzwk5vIsifBV kRFWAZstAI04TQlaE2DU7AFMWi4WHh06ScpaWOL2eNT4wSDNU6JlxdF0msKNI5A+ aoKkEEOoI4u85SFbttqPdB1PiBtTClv8mB68ollw4MzUcKbmF5byR56KeCUsT0Wo NaaXlLiMBEPquqaRHac+3DTRemZkoSQGQyLhXBahra6RN5d2SE7WMeJMvBcc8fGr MFgEdiU20rUSZGYmmhwY =wIOu -----END PGP SIGNATURE-----
