Lars Michael <lh_post <at> yahoo.com> writes: At the same time we noticed (by using strace) that there is an excessive and continously sequence of system calls at normal program execusion: 333 (__NR_GET_THREAD_AREA), and 335 (__NR_ATOMIC_CMPXCHG_32) Thorsten Glaser <tg@xxxxxxxxxx> wrote: Yes, that is in fact normal. If you stop using programs (and libraries) that use TLS (thread-local storage) and atomics, you’ll notice a massive speedup as these syscalls will no longer be issued. The only way out of this is an ABI breakage, with at least * set one CPU register aside for the TLS base * add a VDSO or some other kind of page for “fast syscalls”, to optimise away the need for cmpxchg to call into the kernel (if possible), and maybe speed up e.g. gettimeofday * bump time_t to 64 bit (pet peeve of mine) * … maybe others? I’m not a Linux kernel coder. Thorsten, thanks for commenting. I am not really familiar with all this, but given what you say is true, is it fair to say that the ColdFire v4 is a 'less optimal' processor for running Linux? A thing to add is that there are no free register left for a TLS base. Does anybody have really good experience with running Linux on the v4? Thanks Lars Horvath -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
