Subject: Re: Strange libc shared vs. unshared performance
To: Chris G. Demetriou <cgd@alpha.bostic.com>
From: Dennis Ferguson <dennis@mci.net>
List: port-sparc
Date: 11/12/1994 10:00:19
> and why does this surprise you?
>
> if the binary is dynamically linked (i.e. -static is not specified),
> then the dynamic linking must take place!  it takes place when
> the program is stated, and it's quite likely that depending on how
> the program is timed, the dynamic link time is included in the program
> runtime.

Umm, it certainly isn't surprising that the program is slower, but
it should be a little surprising how much slower it is (note that
I haven't reproduced these numbers, just looked at the ones which
were offered).  In the static case he got

>> Please give the number of runs through the benchmark: 500000
[...]
>> Dhrystones per Second:                         25020.2

I.e. the program ran for just under 20 seconds.  In the dynamic case
he got

>> Please give the number of runs through the benchmark: 500000
[...]
>> Dhrystones per Second:                          8801.3

or about 57 seconds for the run.

Would you really expect it to take 37 seconds to dynamically link
this program?  The benchmark isn't all that large.

Dennis Ferguson