tomc@oakhill.UUCP (Tom Cunningham) (10/16/87)
We have VAX C 2.3 on a VAX 750 running VMS 4.5. I am rather surprised
at the compilation speeds. The compiler took 2 1/2 minutes to compile
a 2000 line C program using the /NOOPTIMIZE and /DEBUG options. On an
IBM PC/AT running DOS 3.2 with Microsoft C 4.00 the same program compiles
in just under 2 minutes using large model and default optimization.
Now I realize this is comparing apples and oranges, but I never thought
a PC would beat a VAX, even a 750, particularly since a Sun 3/50 blows
both of these away (compilation in less than a minute). All of these
machines may use wildly different compiler technology and that may be
the root of the issue. Or perhaps our VAX just needs a tuneup (stat()
calls seem to take an inordinate amount of time to service). Any comments?
--
Tom Cunningham "On the ragged edge of technology."
USPS: Motorola Inc. 6501 William Cannon Dr. W. Austin,TX 78735-8598
UUCP: {ihnp4,seismo,ctvax,gatech}!ut-sally!oakhill!tomc
sun!oakhill!tomctomc@oakhill.UUCP (Tom Cunningham) (10/16/87)
In article <1021@oakhill.UUCP>, tomc@oakhill.UUCP (Tom Cunningham) writes: > > We have VAX C 2.3 on a VAX 750 running VMS 4.5. I am rather surprised > at the compilation speeds. The compiler took 2 1/2 minutes to compile > a 2000 line C program using the /NOOPTIMIZE and /DEBUG options. On an > IBM PC/AT running DOS 3.2 with Microsoft C 4.00 the same program compiles > in just under 2 minutes using large model and default optimization. > I forgot to mention that I was the only user on the VAX at the time I did these compiles, and there were no batch jobs running, so it was not very heavily loaded. -- Tom Cunningham "On the ragged edge of technology." USPS: Motorola Inc. 6501 William Cannon Dr. W. Austin,TX 78735-8598 UUCP: {ihnp4,seismo,ctvax,gatech}!ut-sally!oakhill!tomc sun!oakhill!tomc
henry@utzoo.UUCP (Henry Spencer) (10/19/87)
> Now I realize this is comparing apples and oranges, but I never thought > a PC would beat a VAX, even a 750, particularly since a Sun 3/50 blows > both of these away (compilation in less than a minute)... The 750 is a much-overrated processor. It is in fact a little slower than a pdp11/44, and I think a well-configured AT is a bit faster than a 44. It is no surprise that a 3/50 does much better than either -- its cpu is 3-4 times as fast. I/o configuration does also enter the picture, of course. As does compiler technology: the PC compilers quite possibly put more emphasis on fast compilation (since the PC is useless for anything else while the compiler is running) while minicomputer compilers generally work harder on code quality. -- "Mir" means "peace", as in | Henry Spencer @ U of Toronto Zoology "the war is over; we've won". | {allegra,ihnp4,decvax,utai}!utzoo!henry