From: Brian Warner Date: Tue, 7 Apr 2009 21:15:14 +0000 (-0700) Subject: NEWS: format some (but not all) items X-Git-Tag: allmydata-tahoe-1.4.0~19 X-Git-Url: https://git.rkrishnan.org/components/provisioning?a=commitdiff_plain;h=4b2f6fc0985280cb0ac3c650c43b06f7cf366f96;p=tahoe-lafs%2Ftahoe-lafs.git NEWS: format some (but not all) items --- diff --git a/NEWS b/NEWS index 203d5323..b6d9c2b9 100644 --- a/NEWS +++ b/NEWS @@ -3,34 +3,122 @@ User visible changes in Tahoe. -*- outline -*- * Release ? (?) ** Garbage Collection -1.3.0 servers return exception for unknown SI - 1.3.0 clients emit Incident + +The big feature for this release is the implementation of garbage collection, +allowing Tahoe storage servers to delete shares for old deleted files. When +enabled, this uses a "mark and sweep" process: clients are responsible for +updating the leases on their shares (generally by running "tahoe deep-check +--add-lease"), and servers are allowed to delete any share which does not +have an up-to-date lease. The process is described in detail in +docs/garbage-collection.txt . + +The server must be configured to enable garbage-collection, by adding +directives to the [storage] section that define an age limit for shares. The +default configuration will not delete any shares. + +Both servers and clients should be upgraded to this release to make the +garbage-collection as pleasant as possible. 1.2.0 servers do not have the +code to perform the update-lease operation, while 1.3.0 servers have +update-lease but will return an exception for unknown storage indices, +causing clients to emit an Incident for each exception, slowing the add-lease +process down to a crawl. 1.3.0 clients did not have the add-lease operation +at all. + +** Security/Usability Problems Fixed + +The previous codebase permitted a small timing attack (due to our use of +strcmp) against the write-enabler and lease-renewal/cancel secrets. An +attacker who could measure response-time variations of approximatly 3ns +against a very noisy background time of about 15ms might be able to guess +these secrets. We do not believe this attack was actually feasible. This +release closes the attack by first hashing the two strings to be compared +with a random secret. + +A super-linear algorithm in the Merkle Tree code was fixed, which previously +caused e.g. download of a 10GB file to take several hours before the first +byte of plaintext could be produced. The new "alacrity" is about 2 minutes. A +future release should reduce this to a few seconds by fixing ticket #442. + +** webapi changes + +In most cases, HTML tracebacks will only be sent if an "Accept: text/html" +header was provided with the HTTP request. This will generally cause browsers +to get an HTMLized traceback but send regular text/plain tracebacks to +non-browsers (like the CLI clients). More errors have been mapped to useful +HTTP error codes. + +The streaming webapi operations (deep-check and manifest) now have a way to +indicate errors (an output line that starts with "ERROR" instead of being +legal JSON). See docs/frontends/webapi.txt for details. + +The storage server now has its own status page (at /storage), linked from the +Welcome page. This page shows progress and results of the two new +share-crawlers: one which merely counts shares (to give an estimate of how +many files/directories are being stored in the grid), the other examines +leases and reports how much space would be freed if GC were enabled. The page +also shows how much disk space is present, used, reserved, and available for +the Tahoe server, and whether the server is currently running in "read-write" +mode or "read-only" mode. + +** CLI changes + +"tahoe check" and "tahoe deep-check" now accept an "--add-lease" argument, to +update a lease on all shares. This is the "mark" side of garbage collection. + +In many cases, CLI error messages have been improved: the ugly HTMLized +traceback has been replaced by a normal python traceback. + +"tahoe deep-check" and "tahoe manifest" now have better error reporting. + +"tahoe backup" now accepts several "--exclude" arguments, to ignore certain +files (like editor temporary files and version-control metadata) during +backup. + +On windows, the CLI now accepts local paths like "c:\dir\file.txt", which +previously was interpreted as a Tahoe path using a "c:" alias. + +The "tahoe restart" command now uses "--force" by default (meaning it will +start a node even if it didn't look like there was one already running). + +"tahoe cp -r --caps-only tahoe:dir localdir" is a diagnostic tool which, +instead of copying the full contents of files into the local directory, +merely copies their filecaps. This can be used to verify the results of a +"consolidation" operation. + +** other fixes + +The codebase no longer rauses RuntimeError as a kind of assert(). Specific +exception classes were created for each previous instance of RuntimeError. + +Many unit tests were changed to use a non-network test harness, speeding them +up considerably. + ** misc lossmodel, /reliability page (needs numpy) -no-network test harness, speed up tests -streaming deep-check webapi, 'tahoe deep-check'. ERROR line. -improve CLI error messages for "manifest" and "deep-check" -remote_add_lease exits silently for unknown SI -add --add-lease to 'tahoe check' and 'tahoe deep-check', webapi -expand storage status page: show reserved_space, share-counting crawler, - expiration crawler -add --exclude, --exclude-from, --exclude-vcs to 'tahoe backup -stop using RuntimeError -windows: make CLI tolerate "c:\dir\file.txt", instead of thinking "c:" is an - alias -"tahoe restart": make --force the default -#645 sftp path-handling logic -use Accept: header to control HTML-vs-text/plain tracebacks +#no-network test harness, speed up tests +#streaming deep-check webapi, 'tahoe deep-check'. ERROR line. +#improve CLI error messages for "manifest" and "deep-check" +#remote_add_lease exits silently for unknown SI +#add --add-lease to 'tahoe check' and 'tahoe deep-check', webapi +#expand storage status page: show reserved_space, share-counting crawler, +# expiration crawler +#add --exclude, --exclude-from, --exclude-vcs to 'tahoe backup' +#stop using RuntimeError +#windows: make CLI tolerate "c:\dir\file.txt", instead of thinking "c:" is an +# alias +#"tahoe restart": make --force the default + #645 sftp path-handling logic +#use Accept: header to control HTML-vs-text/plain tracebacks make "tahoe cp" less verbose by default when dirnode can't be read, emit minimal webapi page with more-info links -improve CLI error messages: fewer HTML tracebacks +#improve CLI error messages: fewer HTML tracebacks "tahoe debug consolidate" CLI command deep-traverse in alphabetical order turn break in deep-traverse to avoid stack overflow -tahoe cp -r --caps-only -fix timing attack against write-enabler, lease-renewal secrets -fix superlinear hashtree code, reduce alacrity of 10GB file from hours to 2min +#tahoe cp -r --caps-only +#fix timing attack against write-enabler, lease-renewal secrets +#fix superlinear hashtree code, reduce alacrity of 10GB file from hours to 2min * Release 1.3.0 (2009-02-13)