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List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: guix-devel-bounces+larch=yhetil.org@gnu.org X-Migadu-Flow: FLOW_IN X-Migadu-Country: US X-Migadu-Spam-Score: -7.83 X-Spam-Score: -7.83 X-Migadu-Queue-Id: 51DCF5C474 X-Migadu-Scanner: mx13.migadu.com X-TUID: uCQXMfV1WXCO Hi, Ricardo Wurmus skribis: > to me the biggest downside of using =E2=80=9Cguix time-machine=E2=80=9D i= s that it has > to do a lot of boring work before the interesting work begins. The > boring work includes building Guix derivations for the given channels, > most of which have long been collected as garbage on ci.guix.gnu.org. > > It would be helpful, I think, to more aggressively cache these > derivations and their outputs, and to go back in time and build the > derivatinons for past revisions of Guix. I would expect there to be a > lot of overlap in the produced files, so perhaps it won=E2=80=99t cost al= l that > much in terms of storage. > > What do you think? I agree. The =E2=80=98guix publish=E2=80=99 TTL=C2=B9 at ci.guix was incre= ased to 180 days following in 2021. That=E2=80=99s stil= l not that much and these days and right now we have 84=C2=A0TiB free at ci.guix. I guess we can afford increasing the TTL, probably starting with, say, 300 days, and monitoring disk usage. WDYT? For longer-term storage though, we=E2=80=99ll need a solution like what Sim= on described, offered by university colleagues. I=E2=80=99m not sure why this particular effort stalled; we should check with whoever spearheaded it and see if we can resume. Thanks, Ludo=E2=80=99. =C2=B9 That=E2=80=99s the time-to-live, which denotes the minimum time a su= bstitute is kept. Anytime a substitute is queried, its =E2=80=9Cage=E2=80=9D is r= eset; if nobody asks for it, it may be reclaimed after its TTL has expired.