3 ms·
Oh interesting. TIL.
by arielweisberg 9y ago
Oh interesting. TIL.
- bonzini 9y agoActually it depends on the processor. Nowadays it's rare, but in the past there used to be software TLBs where a TLB miss did trap into the kernel, and there was no radix tree-like page table structure in the definition of the architecture. SPARC and MIPS for example worked like this, and server POWER chips had a hashed page table that many OSes populated lazily, effectively treating it like a (more efficient) software TLB.
- namibj 9y agoWell, MIPS is still in widespread use in wifi hardware, and POWER is being resurrected for a scale-up way to deal with a growing database, considering the current generation scales higher at about a similar pricepoint than a 4-socket Intel machine. So I am not sure what the past tense is supposed to mean, if it denotes the architectures to no longer compromise a significant part of world-wide (say DRYSTONE) MIPS, or their lack of use where they are good at (false).
- bonzini 9y agoI am not sure about MIPS, but other processors have moved away from either software TLBs or hashed page tables (POWER9 supports tree page tables). Hence the past tense.