On Mon, Nov 09, 2009 at 09:57:43AM +0100, Tobias Oetiker wrote: > Hi Kevin, > > since 1.4.x is now out, I would like to hold off on adding new > public functions to the 1.4 branche ... these would go into the new > trunk. or is there also a bug-fix component to this change ?
Tobi, This improves performance for implementations where realloc() may be expensive.. It causes the realloc() for cache_item_t.values to be in larger chunks, and less frequent. This is in response to Thorsten's performance testing, where he sees CPU spikes at specific times after start-up, when his cache_item_t.values arrays all simultaneously cross some size threshold. Up to you. -- kevin brintnall =~ /kbr...@rufus.net/ > cheers > tobi > > Oct 31 kevin brintnall wrote: > > > --- > > doc/librrd.pod | 18 ++++++++++++++++++ > > src/rrd.h | 4 ++++ > > src/rrd_utils.c | 53 > > ++++++++++++++++++++++++++++++++++++++++++----------- > > 3 files changed, 64 insertions(+), 11 deletions(-) > > > > diff --git a/doc/librrd.pod b/doc/librrd.pod > > index 038746c..396e50c 100644 > > --- a/doc/librrd.pod > > +++ b/doc/librrd.pod > > @@ -81,6 +81,16 @@ end of the new C<dest>. Returns 1 on success, 0 on > > failure. > > if (!rrd_add_ptr(&arr, &arr_size, elem)) > > handle_failure(); > > > > +=item B<rrd_add_ptr_chunk(void ***dest, size_t *dest_size, void *src, > > size_t *alloc, size_t chunk)> > > + > > +Like C<rrd_add_ptr>, except the destination is allocated in chunks of > > +C<chunk>. C<alloc> points to the number of entries allocated, whereas > > +C<dest_size> points to the number of valid pointers. If more pointers are > > +needed, C<chunk> pointers are allocated and C<alloc> is increased > > +accordingly. C<alloc> must be E<gt>= C<dest_size>. > > + > > +This method improves performance on hosts with expensive C<realloc()>. > > + > > =item B<rrd_add_strdup(char ***dest, size_t *dest_size, char *src)> > > > > Like C<rrd_add_ptr>, except adds a C<strdup> of the source string. > > @@ -91,6 +101,14 @@ Like C<rrd_add_ptr>, except adds a C<strdup> of the > > source string. > > if (!rrd_add_strdup(&arr, &arr_size, str)) > > handle_failure(); > > > > +=item B<rrd_add_strdup_chunk(char ***dest, size_t *dest_size, char *src, > > size_t *alloc, size_t chunk)> > > + > > +Like C<rrd_add_strdup>, except the destination is allocated in chunks of > > +C<chunk>. C<alloc> points to the number of entries allocated, whereas > > +C<dest_size> points to the number of valid pointers. If more pointers are > > +needed, C<chunk> pointers are allocated and C<alloc> is increased > > +accordingly. C<alloc> must be E<gt>= C<dest_size>. > > + > > =item B<rrd_free_ptrs(void ***src, size_t *cnt)> > > > > Free an array of pointers allocated by C<rrd_add_ptr> or > > diff --git a/src/rrd.h b/src/rrd.h > > index ce7e749..6008794 100644 > > --- a/src/rrd.h > > +++ b/src/rrd.h > > @@ -333,8 +333,12 @@ int rrd_proc_start_end( > > > > long rrd_random(void); > > > > + int rrd_add_ptr_chunk(void ***dest, size_t *dest_size, void *src, > > + size_t *alloc, size_t chunk); > > int rrd_add_ptr(void ***dest, size_t *dest_size, void *src); > > int rrd_add_strdup(char ***dest, size_t *dest_size, char *src); > > + int rrd_add_strdup_chunk(char ***dest, size_t *dest_size, char *src, > > + size_t *alloc, size_t chunk); > > void rrd_free_ptrs(void ***src, size_t *cnt); > > > > int rrd_mkdir_p(const char *pathname, mode_t mode); > > diff --git a/src/rrd_utils.c b/src/rrd_utils.c > > index 3936cff..6853c66 100644 > > --- a/src/rrd_utils.c > > +++ b/src/rrd_utils.c > > @@ -50,29 +50,53 @@ long rrd_random(void) > > return random(); > > } > > > > -/* rrd_add_ptr: add a pointer to a dynamically sized array of pointers, > > - * realloc as necessary. returns 1 on success, 0 on failure. > > +/* rrd_add_ptr_chunk: add a pointer to a dynamically sized array of > > + * pointers, realloc as necessary in multiples of "chunk". > > + * > > + * "alloc" is the number of pointers allocated > > + * "dest_size" is the number of valid pointers > > + * > > + * returns 1 on success, 0 on failure. > > */ > > > > -int rrd_add_ptr(void ***dest, size_t *dest_size, void *src) > > +int rrd_add_ptr_chunk(void ***dest, size_t *dest_size, void *src, > > + size_t *alloc, size_t chunk) > > { > > void **temp; > > > > assert(dest != NULL); > > + assert(alloc != NULL); > > + assert(*alloc >= *dest_size); > > > > - temp = (void **) rrd_realloc(*dest, (*dest_size+1) * sizeof(*dest)); > > - if (!temp) > > - return 0; > > + if (*alloc == *dest_size) > > + { > > + temp = (void **) rrd_realloc(*dest, (*alloc+chunk) * > > sizeof(*dest)); > > + if (!temp) > > + return 0; > > > > - *dest = temp; > > - temp[*dest_size] = src; > > + *dest = temp; > > + *alloc += chunk; > > + } > > + > > + (*dest)[*dest_size] = src; > > (*dest_size)++; > > > > return 1; > > } > > > > -/* like rrd_add_ptr, but calls strdup() on a string first. */ > > -int rrd_add_strdup(char ***dest, size_t *dest_size, char *src) > > +/* rrd_add_ptr: add a pointer to a dynamically sized array of pointers, > > + * realloc as necessary. returns 1 on success, 0 on failure. > > + */ > > +int rrd_add_ptr(void ***dest, size_t *dest_size, void *src) > > +{ > > + size_t alloc = *dest_size; > > + > > + return rrd_add_ptr_chunk(dest, dest_size, src, &alloc, 1); > > +} > > + > > +/* like rrd_add_ptr_chunk, but calls strdup() on a string first. */ > > +int rrd_add_strdup_chunk(char ***dest, size_t *dest_size, char *src, > > + size_t *alloc, size_t chunk) > > { > > char *dup_src; > > int add_ok; > > @@ -84,13 +108,20 @@ int rrd_add_strdup(char ***dest, size_t *dest_size, > > char *src) > > if (!dup_src) > > return 0; > > > > - add_ok = rrd_add_ptr((void ***)dest, dest_size, (void *)dup_src); > > + add_ok = rrd_add_ptr_chunk((void ***)dest, dest_size, (void *)dup_src, > > alloc, chunk); > > if (!add_ok) > > free(dup_src); > > > > return add_ok; > > } > > > > +int rrd_add_strdup(char ***dest, size_t *dest_size, char *src) > > +{ > > + size_t alloc = *dest_size; > > + > > + return rrd_add_strdup_chunk(dest, dest_size, src, &alloc, 1); > > +} > > + > > void rrd_free_ptrs(void ***src, size_t *cnt) > > { > > void **sp; > > > > -- > Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland > http://it.oetiker.ch t...@oetiker.ch ++41 62 775 9902 / sb: -9900 _______________________________________________ rrd-developers mailing list rrd-developers@lists.oetiker.ch https://lists.oetiker.ch/cgi-bin/listinfo/rrd-developers