----- 23 cze 2020 o 19:24, Andrew Cooper andrew.coop...@citrix.com napisał(a): > On 23/06/2020 09:51, Jan Beulich wrote: >> I'd still like to see an explicit confirmation by him that this >> use of memory is indeed what he has intended. There are much smaller >> amounts of memory which we allocate on demand, just to avoid >> allocating some without then ever using it. > > PT is a debug/diagnostic tool. Its not something you'd run in > production against a production VM. > > It's off by default (by virtue of having to explicitly ask to use it in > the first place), and those who've asked for it don't want to be finding > -ENOMEM after the domain has been running for a few seconds (or midway > through the vcpus), when they inveterately want to map the rings. > > Those who request buffers in the first place and forget about them are > not semantically different from those who ask for a silly shadow memory > limit, or typo the guest memory and give it too much. Its a admin > error, not a safety/correctness issue. > > ~Andrew
Absolutely +1. Assuming that somebody wants to perform some advanced scenario and is trying to run many domains (e.g. 20), it's much better to have 19 domains working fine and 1 prematurely crashing because of -ENOMEM, rather than have all 20 domains randomly crashing in runtime because it turned out there is a shortage of memory. Best regards, Michał Leszczyński CERT Polska
