syslink effort update

Jan Mikkelsen janm at
Sun Apr 29 16:57:43 PDT 2007

Matthew Dillon wrote:
>    Well, only if GCC were to support 128 bit integers.  The real issue
>    here is memory overhead.  64 bits is already 8 bytes, 128 bits
>    is 16 bytes.  Plus cpu overhead for initializing and processing it all.
>    I don't think its a big deal, though, so yes: We could use 128 bits if
>    we needed to.  I'm going to try to keep things in 64 bits for now but
>    it could very well be that 128 bits will be more workable in a cluster
>    environment, allowing the per-host sysids to be expanded into 
> cluster-wide
>    unique sysids with very little effort.

There is __int128_t.

janm at janm-i386: ~ $ gcc --version
gcc (GCC) 3.4.6 [FreeBSD] 20060305
janm at janm-i386: ~ $ cat jan.c
#include <stdio.h>
int main() { printf("sizeof(__int128_t) == %d\n", sizeof(__int128_t)); }
janm at janm-i386: ~ $ cc jan.c
janm at janm-i386: ~ $ ./a.out
sizeof(__int128_t) == 16



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