X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/5575de140d17f201f370fe6a1ea091c5ee592800..a6a3c3df453f0551e68f08ef3a15d015848b8695:/TODO diff --git a/TODO b/TODO index 438aa995..75d4e56a 100644 --- a/TODO +++ b/TODO @@ -35,12 +35,91 @@ use chroot Performance Traverse just one directory at a time. Tridge says it's possible. - - Can possibly also be smarter about memory use while looking for hard - links by reducing the refcount as we find alternative names. + + At the moment rsync reads the whole file list into memory at the + start, which makes us use a lot of memory and also not pipeline + network access as much as we could. + +Memory accounting + + At exit, show how much memory was used for the file list, etc. + +Hard-link handling + + At the moment hardlink handling is very expensive, so it's off by + default. It does not need to be so. + + We can rule out hardlinked directories since they will probably + screw us up in all kinds of ways. They simply should not be used. + + At the moment rsync only cares about hardlinks to regular files. I + guess you could also use them for sockets, devices and other beasts, + but I have not seen them. + + When trying to reproduce hard links, we only need to worry about + files that have more than one name (nlinks>1 && !S_ISDIR). + + The basic point of this is to discover alternate names that refer to + the same file. All operations, including creating the file and + writing modifications to it need only to be done for the first name. + For all later names, we just create the link and then leave it + alone. + + If hard links are to be preserved: + + Before the generator/receiver fork, the list of files is received + from the sender (recv_file_list), and a table for detecting hard + links is built. + + The generator looks for hard links within the file list and does + not send checksums for them, though it does send other metadata. + + The sender sends the device number and inode with file entries, so + that files are uniquely identified. + + The receiver goes through and creates hard links (do_hard_links) + after all data has been written, but before directory permissions + are set. + + At the moment device and inum are sent as 4-byte integers, which + will probably cause problems on large filesystems. On Linux the + kernel uses 64-bit ino_t's internally, and people will soon have + filesystems big enough to use them. We ought to follow NFS4 in + using 64-bit device and inode identification, perhaps with a + protocol version bump. + + Once we've seen all the names for a particular file, we no longer + need to think about it and we can deallocate the memory. + + We can also have the case where there are links to a file that are + not in the tree being transferred. There's nothing we can do about + that. Because we rename the destination into place after writing, + any hardlinks to the old file are always going to be orphaned. In + fact that is almost necessary because otherwise we'd get really + confused if we were generating checksums for one name of a file and + modifying another. + + At the moment the code seems to make a whole second copy of the file + list, which seems unnecessary. + + We should have a test case that exercises hard links. Since it + might be hard to compare ./tls output where the inodes change we + might need a little program to check whether several names refer to + the same file. IPv6 + Implement suggestions from http://www.kame.net/newsletter/19980604/ + and ftp://ftp.iij.ad.jp/pub/RFC/rfc2553.txt + + If a host has multiple addresses, then listen try to connect to all + in order until we get through. (getaddrinfo may return multiple + addresses.) This is kind of implemented already. + + Possibly also when starting as a server we may need to listen on + multiple passive addresses. This might be a bit harder, because we + may need to select on all of them. Hm. + Define a syntax for IPv6 literal addresses. Since they include colons, they tend to break most naming systems, including ours. Based on the HTTP IPv6 syntax, I think we should use @@ -70,6 +149,27 @@ File attributes Probably better not to even try to convert between NT and POSIX. Possibly can share some code with Samba. +Empty directories + + With the current common --include '*/' --exclude '*' pattern, people + can end up with many empty directories. We might avoid this by + lazily creating such directories. + +zlib + + Perhaps don't use our own zlib. Will we actually be incompatible, + or just be slightly less efficient? + +logging + + Perhaps flush stdout after each filename, so that people trying to + monitor progress in a log file can do so more easily. See + http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=48108 + +rsyncd over ssh + + There are already some patches to do this. + PLATFORMS ------------------------------------------------------------ Win32 @@ -85,6 +185,10 @@ Win32 we are correct to call close(), because shutdown() discards untransmitted data. +DOCUMENTATION -------------------------------------------------------- + +Update README + BUILD FARM ----------------------------------------------------------- Add machines @@ -99,6 +203,10 @@ Add machines NICE ----------------------------------------------------------------- +SIGHUP + + Re-read config file (just exec() ourselves) rather than exiting. + --no-detach and --no-fork options Very useful for debugging. Also good when running under a @@ -109,6 +217,10 @@ hang/timeout friendliness On +verbose output + + Indicate whether files are new, updated, or deleted + internationalization Change to using gettext(). Probably need to ship this for platforms