On Sat, Apr 27, 2019 at 04:43:14PM +0200, Otto Moerbeek wrote:
> 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.
And the do on amd64
>
> -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
> >
>
