diff --git a/Summit2Day3.md b/Summit2Day3.md new file mode 100644 index 0000000..2b39ef3 --- /dev/null +++ b/Summit2Day3.md @@ -0,0 +1,56 @@ +# [2nd Summit](Summit) Day 3 + +10-Nov-2011, Mozilla SF. + +No video due to technical problems. + +## Attendees +* Zooko +* David-Sarah +* Zancas +* Brian +* Bill Frantz +* Sam Stoller + +## Goals + +* David-Sarah to present LAE's s3-backend branch +* figure out merge plan for s3-backend and accounting +* figure out leasedb crawler: detailed case analysis + +## Topics + +* (one-person) Tahoe InstallFest! + * successfully got Tahoe installed on Bill Frantz's laptop. Excitement + ensued from its lack of XCode and gcc. Eggs were built and + installation proceeded smoothly. +* (one-person) LAE Customer Setup! + * successfully (eventually) got Brian signed up as an LAE customer. + Kinda neat to include a PGP fingerprint on a signup form. Succeeded + in uploading a (small) test file. +* quick review of LAE's s3-backend branch (davidsarah) + * brian hesitant about apparent complexity, but mitigated by the + pre-existing messy complexity of the non-pluggable-backend code. + * all parties looking forward to ripping out lease code and replacing + with whatever comes out of brian's Accounting project + * s3 backend currently has memory-footprint problems with large shares + * branch also includes extra cleanups: + `twisted.python.filepath`-ification, whitespace cleanups, + `Interface`-de-parameterization, client-side comment fixes. + Hopefully these will turn into separate patches which can be landed + separately. +* discussion of mutable-file CAP stuff + * proposal to use two-phase commit and locking to improve mutable-file + data preservation + * general idea would be that servers allow one client to lock the next + version of a share (for some limited time), then clients obtain lock + on all shares before committing to a change. If clients observe + contention (i.e. they are refused a lock because some second client + already grabbed it), abandon all locks and back off. + * additional idea: servers retain previous version of share until a + third phase lets them delete it. Clients obtain lock, upload+commit + to v2, when all servers report success, clients delete v1. Some + failure cases result in mix of (v1-only) and (v1+v2) servers. Repair + would need to spot these and be able to roll back to v1. Servers + would need to report all versions that had been committed. Readers + could see v1 and v2 and deliver v1 if v2 is not recoverable.