Re:This shouldn't have happened: A vulnerability postmortem
by titzer on Wednesday December 01, 2021 @11:06PM
(#29412460)
Have you measured the pause times of free()? Because they are not deterministic, and I have met few people who understand in detail how complex it can be in practice. In the limit, free() can be as bad as GC pause times because of chained deallocation--i.e. not statically bounded.
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Re:This shouldn't have happened: A vulnerability postmortem
by gpderetta on Thursday December 02, 2021 @03:26AM
(#29413762)
People don't call free from their realtime threads.
Re:This shouldn't have happened: A vulnerability postmortem
by alophawen on Thursday December 02, 2021 @02:36AM
(#29413506)
This is true, but for performance's sake, you should not alloc/free in a busy loop, especially not on a real time system.
Allocate in advance, reuse allocated memory.
Re:This shouldn't have happened: A vulnerability postmortem
by titzer on Monday December 06, 2021 @08:54AM
(#29459733)
> Allocate in advance, reuse allocated memory.
In practice, almost all real-time systems use this strategy, even going so far as to allocate all memory at compile time. The first versions of Virgil (I and II) used this strategy and compiled to C.
When doing this, the whole debate of memory safe (automatic) vs unsafe (manual) is completely orthogonal.