On 2015-07-30 05:52, Dennis Luehring wrote: > Am 29.07.2015 um 17:01 schrieb Aurelien Jarno: > >The point is that emulation has a cost, and it's quite difficult to > >to lower it and thus improve the emulation speed. > > so its just not strange for you to see an 1/100...200 of the native x64 > speed under qemu/SPARC64 > i hoped that someone will jump up an shout "its impossible - it needs to be > a bug" ...sadly not
Overall the ratio is more around 10, but in some specific cases where the TB cache is inefficient and TB can't be linked or with an inefficient MMU, a ratio of 100 is possible. Also remember you are comparing apples and oranges there. A GCC compiler for x86-64 and for SPARC64 can't really be compared, even if the front-end and middle-end part are the same. The job of generating the assembly code is not the same and might take more or less time depending on the architecture complexity. Finally make sure you have enough RAM in your guest and that GCC isn't swapped. Recent GCC versions needs a lot of memory and the default 128MB might not be enough. -- Aurelien Jarno GPG: 4096R/1DDD8C9B aurel...@aurel32.net http://www.aurel32.net
