fluencelabs/redis
1
0
Fork 0
mirror of https://github.com/fluencelabs/redis synced 2025-06-25 06:51:32 +00:00
Code Issues Projects Releases Wiki Activity

Add zcalloc and use it where appropriate

Browse Source 
calloc is more effecient than malloc+memset when the system uses mmap to
allocate memory. mmap always returns zeroed memory so the memset can be
avoided.  The threshold to use mmap is 16k in osx libc and 128k in bsd
libc and glibc. The kernel can lazily allocate the pages, this reduces
memory usage when we have a page table or hash table that is mostly
empty.

This change is most visible when you start a new redis instance with vm
enabled.  You'll see no increased memory usage no matter how big your
page table is.
This commit is contained in:
Benjamin Kramer
2010-07-24 23:20:00 +02:00
parent d9dd352b36
commit 399f2f401c
4 changed files with 18 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
src/dict.c
View File

@ -148,14 +148,12 @@ int dictExpand(dict *d, unsigned long size)
if (dictIsRehashing(d) || d->ht[0].used > size)
return DICT_ERR;
/* Allocate the new hashtable and initialize all pointers to NULL */
n.size = realsize;
n.sizemask = realsize-1;
n.table = zmalloc(realsize*sizeof(dictEntry*));
n.table = zcalloc(realsize*sizeof(dictEntry*));
n.used = 0;
/* Initialize all the pointers to NULL */
memset(n.table, 0, realsize*sizeof(dictEntry*));
/* Is this the first initialization? If so it's not really a rehashing
* we just set the first hash table so that it can accept keys. */
if (d->ht[0].table == NULL) {