Sat Apr 24 13:44:44 Paris, Madrid (heure d'été) 2010 freestorm77@gmail.com * doc_reformat_performance.txt - Added heading format begining and ending by "==" - Added Index - Added Title Note: No change are made in paragraphs content New patches: [doc_reformat_performance.txt freestorm77@gmail.com**20100424114444 Ignore-this: 55295ff5cd8a5b67034eb661a5b0699d - Added heading format begining and ending by "==" - Added Index - Added Title Note: No change are made in paragraphs content ] { hunk ./docs/performance.txt 3 = Performance costs for some common operations = -=== Publishing an A-byte immutable file === +1. Publishing an A-byte immutable file +2. Publishing an A-byte mutable file +3. Downloading B bytes of an A-byte immutable file +4. Downloading B bytes of an A-byte mutable file +5. Modifying B bytes of an A-byte mutable file +6. Inserting/Removing B bytes in an A-byte mutable file +7. Adding an entry to an A-entry directory +8. Listing an A entry directory +9. Performing a file-check on an A-byte file +10. Performing a file-verify on an A-byte file +11. Repairing an A-byte file (mutable or immutable) + +== Publishing an A-byte immutable file == network: A memory footprint: N/k*128KiB hunk ./docs/performance.txt 25 encryption derives the encryption key in part from the contents of the source file. -=== Publishing an A-byte mutable file === +== Publishing an A-byte mutable file == network: A memory footprint: N/k*A hunk ./docs/performance.txt 41 Tahoe-LAFS to have an unacceptably large memory footprint (at least when uploading a mutable file). -=== Downloading B bytes of an A-byte immutable file === +== Downloading B bytes of an A-byte immutable file == network: A memory footprint: 128KiB hunk ./docs/performance.txt 63 to read, what part of the file was read by previous reads, and how much time has elapsed since the last read. -=== Downloading B bytes of an A-byte mutable file === +== Downloading B bytes of an A-byte mutable file == network: A memory footprint: A hunk ./docs/performance.txt 72 their entirety before any part of them can be read. We are exploring fixes for this; see ticket #393 for more information. -=== Modifying B bytes of an A-byte mutable file === +== Modifying B bytes of an A-byte mutable file == network: A memory footprint: N/k*A hunk ./docs/performance.txt 85 essentially uploading the file over again, except that it re-uses the existing RSA keypair instead of generating a new one. -=== Inserting/Removing B bytes in an A-byte mutable file === +== Inserting/Removing B bytes in an A-byte mutable file == network: A memory footprint: N/k*A hunk ./docs/performance.txt 100 be modified, as described in "Modifying B bytes of an A-byte mutable file". -=== Adding an entry to an A-entry directory === +== Adding an entry to an A-entry directory == network: O(A) memory footprint: N/k*A hunk ./docs/performance.txt 109 files. So adding an entry to a directory is essentially adding B (actually, 300-330) bytes somewhere in an existing mutable file. -=== Listing an A entry directory === +== Listing an A entry directory == network: O(A) memory footprint: N/k*A hunk ./docs/performance.txt 119 directory requires downloading a (roughly) 330 * A byte mutable file, since each directory entry is about 300-330 bytes in size. -=== Performing a file-check on an A-byte file === +== Performing a file-check on an A-byte file == network: O(S), where S is the number of servers on your grid memory footprint: negligible hunk ./docs/performance.txt 129 of the file. This is relatively inexpensive, compared to the verify and repair operations. -=== Performing a file-verify on an A-byte file === +== Performing a file-verify on an A-byte file == network: N/k*A memory footprint: N/k*128KiB hunk ./docs/performance.txt 140 expensive than downloading an A-byte file, since only a fraction of these shares are necessary to recover the file. -=== Repairing an A-byte file (mutable or immutable) === +== Repairing an A-byte file (mutable or immutable) == network: variable; up to around O(A) memory footprint: from 128KiB to (1+N/k)*128KiB } Context: [docs: install.html http-equiv refresh to quickstart.html zooko@zooko.com**20100421165708 Ignore-this: 52b4b619f9dde5886ae2cd7f1f3b734b ] [docs: install.html -> quickstart.html zooko@zooko.com**20100421155757 Ignore-this: 6084e203909306bed93efb09d0e6181d It is not called "installing" because that implies that it is going to change the configuration of your operating system. It is not called "building" because that implies that you need developer tools like a compiler. Also I added a stern warning against looking at the "InstallDetails" wiki page, which I have renamed to "AdvancedInstall". ] [Fix another typo in tahoe_storagespace munin plugin david-sarah@jacaranda.org**20100416220935 Ignore-this: ad1f7aa66b554174f91dfb2b7a3ea5f3 ] [Add dependency on windmill >= 1.3 david-sarah@jacaranda.org**20100416190404 Ignore-this: 4437a7a464e92d6c9012926b18676211 ] [licensing: phrase the OpenSSL-exemption in the vocabulary of copyright instead of computer technology, and replicate the exemption from the GPL to the TGPPL zooko@zooko.com**20100414232521 Ignore-this: a5494b2f582a295544c6cad3f245e91 ] [munin-tahoe_storagespace freestorm77@gmail.com**20100221203626 Ignore-this: 14d6d6a587afe1f8883152bf2e46b4aa Plugin configuration rename ] [setup: add licensing declaration for setuptools (noticed by the FSF compliance folks) zooko@zooko.com**20100309184415 Ignore-this: 2dfa7d812d65fec7c72ddbf0de609ccb ] [setup: fix error in licensing declaration from Shawn Willden, as noted by the FSF compliance division zooko@zooko.com**20100309163736 Ignore-this: c0623d27e469799d86cabf67921a13f8 ] [CREDITS to Jacob Appelbaum zooko@zooko.com**20100304015616 Ignore-this: 70db493abbc23968fcc8db93f386ea54 ] [desert-island-build-with-proper-versions jacob@appelbaum.net**20100304013858] [docs: a few small edits to try to guide newcomers through the docs zooko@zooko.com**20100303231902 Ignore-this: a6aab44f5bf5ad97ea73e6976bc4042d These edits were suggested by my watching over Jake Appelbaum's shoulder as he completely ignored/skipped/missed install.html and also as he decided that debian.txt wouldn't help him with basic installation. Then I threw in a few docs edits that have been sitting around in my sandbox asking to be committed for months. ] [TAG allmydata-tahoe-1.6.1 david-sarah@jacaranda.org**20100228062314 Ignore-this: eb5f03ada8ea953ee7780e7fe068539 ] Patch bundle hash: 944fac7a5e2209d2b38aed5f92eee9afa9395513