Swap
Swap
Posted May 28, 2021 18:41 UTC (Fri) by faramir (subscriber, #2327)In reply to: Swap by corbet
Parent article: Top-tier memory management
While virtual memory is transparent to the software which is using it, it is not transparent to the system. It requires the system to find some real memory that can be (re)used. This can sometimes be a problem. With NUMA or persistent memory, that isn't a problem. Memory access may still be slower, but at least it will still work without any immediate work by the system.
Posted May 28, 2021 22:31 UTC (Fri)
by MattBBaker (guest, #28651)
[Link]
Swap
The system takes care of that feature too. It's fair to say that if a page was being evicted from DRAM, then on a system with just DRAM it would have been swapped instead. So why not assume that everything in slow space is going to be swapped too. Especially if the slow bank is an HBM space then you can migrate DRAM pages into the HBM banks and once you get HBM_LINE_SIZE pages then page them all out in bulk.