1 patch for repository davidsarah@dev.allmydata.org:/home/darcs/tahoe/trunk: Mon Aug 30 04:26:05 GMT Daylight Time 2010 david-sarah@jacaranda.org * docs/performance.txt, architecture.txt: updates taking into account new downloader. refs #798 New patches: [docs/performance.txt, architecture.txt: updates taking into account new downloader. refs #798 david-sarah@jacaranda.org**20100830032605 Ignore-this: 8c6bd16174d4544157df6f602908426f ] { hunk ./docs/architecture.txt 235 When downloading a file, the current version just asks all known servers for any shares they might have. Once it has received enough responses that it knows where to find the needed k shares, it downloads the shares from those -servers. (This means that it tends to download shares from the fastest -servers.) +servers. This means that it tends to download shares from the fastest +servers. It will prefer to take shares from the first k distinct servers, if +they respond fast enough. *future work* hunk ./docs/performance.txt 43 == Downloading B bytes of an A-byte immutable file == -network: A +network: B memory footprint: 128KiB hunk ./docs/performance.txt 46 -notes: When asked to read an arbitrary range of an immutable file, - Tahoe-LAFS will download from the beginning of the file up until - it has enough of the file to satisfy the requested read. - Depending on where in the file the requested range is, this can - mean that the entire file is downloaded before the request is - satisfied. Tahoe-LAFS will continue to download the rest of the - file even after the request is satisfied, so in any case where the - file actually has to downloaded from the grid, reading part of an - immutable file will result in downloading all of the immutable - file. Ticket #798 is a proposal to change this behavior. +notes: When Tahoe-LAFS 1.8.0 or later is asked to read an arbitrary range + of an immutable file, only the 128-KiB segments that overlap the + requested range will be downloaded. hunk ./docs/performance.txt 50 - Tahoe-LAFS will cache files that are read in this manner for a - short while, so subsequent reads of the same file may be served - entirely from cache, depending on what part of the file they need - to read, what part of the file was read by previous reads, and - how much time has elapsed since the last read. + (Earlier versions would download from the beginning of the file up + until the end of the requested range, and then continue to download + the rest of the file even after the request was satisfied.) == Downloading B bytes of an A-byte mutable file == } Context: [_auto_deps.py: change pycrypto version requirement to avoid https://bugs.launchpad.net/pycrypto/+bug/620253 david-sarah@jacaranda.org**20100829230038 Ignore-this: e58f98ef262444067fc4b31fad23e40b ] [web: refactor rate computation, fixes #1166 francois@ctrlaltdel.ch**20100815141933 Ignore-this: d25491858e137894142eaa67c75b0439 ] [docs: update NEWS a bit about New-Downloader zooko@zooko.com**20100819021446 Ignore-this: 31a6e2fb0a6e3d19f73481e99070da7a ] [misc: add benchmarking tool for spans zooko@zooko.com**20100819021420 Ignore-this: 569327a1908a07e5fb634526bed515b2 ] [docs: doc of the download status page zooko@zooko.com**20100814054117 Ignore-this: a82ec33da3c39a7c0d47a7a6b5f81bbb ref: http://tahoe-lafs.org/trac/tahoe-lafs/ticket/1169#comment:1 ] [docs: NEWS: edit English usage, remove ticket numbers for regressions vs. 1.7.1 that were fixed again before 1.8.0c2 zooko@zooko.com**20100811071758 Ignore-this: 993f5a1e6a9535f5b7a0bd77b93b66d0 ] [docs: NEWS: more detail about new-downloader zooko@zooko.com**20100811071303 Ignore-this: 9f07da4dce9d794ce165aae287f29a1e ] [TAG allmydata-tahoe-1.8.0c2 david-sarah@jacaranda.org**20100810073847 Ignore-this: c37f732b0e45f9ebfdc2f29c0899aeec ] Patch bundle hash: 60cb0a0c6f5e5b9a1c654602d153acbaaf3c3b22