On Sat, Apr 27, 2019 at 04:37:23PM +0200, Antoine Jacoutot wrote:
> On Sat, Apr 27, 2019 at 09:55:33PM +0800, Nathanael Rensen wrote:
> > The diff below speeds up ld.so library intialisation where the dependency
> > tree is broad and deep, such as samba's smbd which links over 100 libraries.
> >
> > See for example https://marc.info/?l=openbsd-misc&m=155007285712913&w=2
> >
> > See https://marc.info/?l=openbsd-tech&m=155637285221396&w=2 for part 1
> > that speeds up library loading.
> >
> > The timings below are for /usr/local/sbin/smbd --version:
> >
> > Timing without either diff : 6m45.67s real 6m45.65s user 0m00.02s system
> > Timing with part 1 diff only: 4m42.88s real 4m42.85s user 0m00.02s system
> > Timing with part 2 diff only: 2m02.61s real 2m02.60s user 0m00.01s system
> > Timing with both diffs : 0m00.03s real 0m00.03s user 0m00.00s system
> >
> > Note that these timings are for a build of a recent samba master tree
> > (linked with kerberos) which is probably slower than the OpenBSD port.
> >
> > Nathanael
>
> Wow. Tried your part1 and part2 diffs and the difference is indeed insane!
> mail/evolution always took 10+ seconds to start for me and now it's almost
> instant...
> Crazy... But this sounds too good to be true ;-)
> What are the potential regressions?
Speaking off regression tests, we have quite en extensive collection.
The tests in libexec/ld.so should all pass.
-Otto
>
>
> > Index: libexec/ld.so/loader.c
> > ===================================================================
> > RCS file: /cvs/src/libexec/ld.so/loader.c,v
> > retrieving revision 1.177
> > diff -u -p -p -u -r1.177 loader.c
> > --- libexec/ld.so/loader.c 3 Dec 2018 05:29:56 -0000 1.177
> > +++ libexec/ld.so/loader.c 27 Apr 2019 13:24:02 -0000
> > @@ -749,15 +749,15 @@ _dl_call_init_recurse(elf_object_t *obje
> > {
> > struct dep_node *n;
> >
> > - object->status |= STAT_VISITED;
> > + int visited_flag = initfirst ? STAT_VISITED_1 : STAT_VISITED_2;
> > +
> > + object->status |= visited_flag;
> >
> > TAILQ_FOREACH(n, &object->child_list, next_sib) {
> > - if (n->data->status & STAT_VISITED)
> > + if (n->data->status & visited_flag)
> > continue;
> > _dl_call_init_recurse(n->data, initfirst);
> > }
> > -
> > - object->status &= ~STAT_VISITED;
> >
> > if (object->status & STAT_INIT_DONE)
> > return;
> > Index: libexec/ld.so/resolve.h
> > ===================================================================
> > RCS file: /cvs/src/libexec/ld.so/resolve.h,v
> > retrieving revision 1.90
> > diff -u -p -p -u -r1.90 resolve.h
> > --- libexec/ld.so/resolve.h 21 Apr 2019 04:11:42 -0000 1.90
> > +++ libexec/ld.so/resolve.h 27 Apr 2019 13:24:02 -0000
> > @@ -125,8 +125,9 @@ struct elf_object {
> > #define STAT_FINI_READY 0x10
> > #define STAT_UNLOADED 0x20
> > #define STAT_NODELETE 0x40
> > -#define STAT_VISITED 0x80
> > +#define STAT_VISITED_1 0x80
> > #define STAT_GNU_HASH 0x100
> > +#define STAT_VISITED_2 0x200
> >
> > Elf_Phdr *phdrp;
> > int phdrc;
> >
>
> --
> Antoine
>
