On Fri, 11 Dec 2009, Nagy Gabor wrote:
-Su is even worse: We have to read all desc files in sync (to get
%REPLACES%)
I changed pacman DB using the following script, and applied the attached
script to pacman so that "pacman -Su" is possible only by reading
"depends" files, not "desc".
for d in $PACDB/sync/*/* $PACDB/local/*
do
sed -ne '/%REPLACES%/,/^$/p' $d/desc >> $d/depends
sed -i -e '/%REPLACES%/,/^$/d' $d/desc
done
The timings I got for the command "pacman -Sup -b $PACDB" are the
following.
Before:
2m15s (cold caches)
0.98s (hot caches)
After:
2m11s (cold caches)
0.78s (hot caches)
Unfortunately it didn't provide such a big improvement as I expected. I
can now justify this because desc files in sync/ were being read *instead*
of depends, not in addition to them. So I _replaced_ the read("*/desc")
with read("*/depends"), but disk seeks are still happening, even for these
smaller files.
I believe big differences will show when people have many upgrades
pending, in which case the already cached depends will come handy.
Unfortunately I only had 6 upgrades pending.
But I think it's vital that not all descriptions and stuff are read during
a common operation like -Su, and with the provided script (run only for
local, since sync should be upgraded on the server) the transition should
be smooth for end-users. What's your opinion?
Dimitris
diff --git a/lib/libalpm/be_files.c b/lib/libalpm/be_files.c
index d09d72a..a6087bd 100644
--- a/lib/libalpm/be_files.c
+++ b/lib/libalpm/be_files.c
@@ -460,12 +460,6 @@ int _alpm_db_read(pmdb_t *db, pmpkg_t *info, pmdbinfrq_t
inforeq)
goto error;
}
STRDUP(info->md5sum, _alpm_strtrim(line), goto
error);
- } else if(strcmp(line, "%REPLACES%") == 0) {
- while(fgets(line, sline, fp) &&
strlen(_alpm_strtrim(line))) {
- char *linedup;
- STRDUP(linedup, _alpm_strtrim(line),
goto error);
- info->replaces =
alpm_list_add(info->replaces, linedup);
- }
} else if(strcmp(line, "%FORCE%") == 0) {
info->force = 1;
}
@@ -528,6 +522,12 @@ int _alpm_db_read(pmdb_t *db, pmpkg_t *info, pmdbinfrq_t
inforeq)
STRDUP(linedup, _alpm_strtrim(line),
goto error);
info->conflicts =
alpm_list_add(info->conflicts, linedup);
}
+ } else if(strcmp(line, "%REPLACES%") == 0) {
+ while(fgets(line, sline, fp) &&
strlen(_alpm_strtrim(line))) {
+ char *linedup;
+ STRDUP(linedup, _alpm_strtrim(line),
goto error);
+ info->replaces =
alpm_list_add(info->replaces, linedup);
+ }
} else if(strcmp(line, "%PROVIDES%") == 0) {
while(fgets(line, sline, fp) &&
strlen(_alpm_strtrim(line))) {
char *linedup;
diff --git a/lib/libalpm/package.c b/lib/libalpm/package.c
index 83a2fb8..387cb1b 100644
--- a/lib/libalpm/package.c
+++ b/lib/libalpm/package.c
@@ -387,8 +387,8 @@ alpm_list_t SYMEXPORT *alpm_pkg_get_replaces(pmpkg_t *pkg)
ASSERT(handle != NULL, return(NULL));
ASSERT(pkg != NULL, return(NULL));
- if(pkg->origin == PKG_FROM_CACHE && !(pkg->infolevel & INFRQ_DESC)) {
- _alpm_db_read(pkg->origin_data.db, pkg, INFRQ_DESC);
+ if(pkg->origin == PKG_FROM_CACHE && !(pkg->infolevel & INFRQ_DEPENDS)) {
+ _alpm_db_read(pkg->origin_data.db, pkg, INFRQ_DEPENDS);
}
return pkg->replaces;
}
