From: Brian Warner Date: Fri, 27 Nov 2009 22:42:17 +0000 (-0500) Subject: NEWS: update with all user-visible changes since the last release X-Git-Url: https://git.rkrishnan.org/pf/content/it.html?a=commitdiff_plain;h=79e7e0d8e33845dbfca7446dad0fb9137847750d;p=tahoe-lafs%2Ftahoe-lafs.git NEWS: update with all user-visible changes since the last release --- diff --git a/NEWS b/NEWS index cb4958d5..869d400b 100644 --- a/NEWS +++ b/NEWS @@ -1,5 +1,70 @@ User visible changes in Tahoe-LAFS. -*- outline -*- +* Release ?.?.? (?) + +** New Features + +*** Immutable Directories + +Tahoe can now create and handle immutable directories. These are read just +like normal directories, but are "deep-immutable", meaning that all their +children (and everything reachable from those children) must be immutable +objects (i.e. immutable/literal files, and other immutable directories). + +These directories must be created in a single webapi call, which provides all +of the children at once (instead of the usual create/add/add sequence, since +they cannot be changed after creation). They have URIs that start with +"URI:DIR2-CHK:" or "URI:DIR2-LIT:", and are described on the human-facing web +interface (aka the "WUI") with a "DIR-IMM" abbreviation (as opposed to "DIR" +for the usual read-write directories and "DIR-RO" for read-only directories). + +Tahoe releases before 1.6.0 cannot read the contents of an immutable +directory. 1.5.0 will tolerate their presence in a directory listing (and +display it as an "unknown node"). 1.4.1 and earlier cannot tolerate them: a +DIR-IMM child in any directory will prevent the listing of that directory. + +Immutable directories are repairable, just like normal immutable files. + +The webapi "POST t=mkdir-immutable" call is used to create immutable +directories. See docs/frontends/webapi.txt for details. + +*** "tahoe backup" now creates immutable directories, backupdb has dircache + +The "tahoe backup" command has been enhanced to create immutable directories +(in previous releases, it created read-only mutable directories). This is +significantly faster, since it does not need to create an RSA keypair for +each new directory. In addition, "DIR-IMM" immutable directories are +repairable, unlike "DIR-RO" read-only mutable directories (at least in this +release; a future Tahoe release should be able to repair DIR-RO). + +In addition, the backupdb (used by "tahoe backup" to remember what it has +already copied) has been enhanced to store information about existing +immutable directories. This allows it to re-use directories that have moved +but still contain identical contents, or which have been deleted and later +replaced. (the 1.5.0 "tahoe backup" command could only re-use directories +that were in the same place as they were in the previous backup). With this +change, the backup process no longer needs to read the previous snapshot out +of the Tahoe grid, reducing the network load considerably. + +As noted above, Tahoe versions earlier than 1.5.0 cannot read immutable +directories. + +** Minor Changes + +The webapi acquired a new "t=mkdir-with-children" command, to create and +populate a directory in a single call. This is significantly faster than +using separate "t=mkdir" and "t=set_children" operations (it uses one +gateway-to-grid roundtrip, instead of three or four). + +The t=set_children operation is now documented in docs/frontends/webapi.txt . + +Several small packaging improvements were made to facilitate the "tahoe-lafs" +package being added to Ubuntu's "Karmic Koala" 9.10 release. Several +mac/win32 binary libraries were removed, some figleaf code-coverage files +were removed, a bundled copy of darcsver-1.2.1 was removed, and additional +licensing text was added. + + * Release 1.5.0 (2009-08-01) ** Improvements