fluencelabs/redis
1
0
Fork 0
mirror of https://github.com/fluencelabs/redis synced 2025-06-15 10:11:21 +00:00
Code Issues Projects Releases Wiki Activity

Object approximated LRU algorithm enhanced / fixed / refactored. This is used for the VM currently but will soon be used for maxmemory expiring.

Browse Source
This commit is contained in:
antirez
2010-10-14 13:52:58 +02:00
parent b4f2e412d0
commit ef59a8bc9e
6 changed files with 41 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
src/redis.c
View File

@ -490,19 +490,15 @@ int serverCron(struct aeEventLoop *eventLoop, long long id, void *clientData) {
* in objects at every object access, and accuracy is not needed.
* To access a global var is faster than calling time(NULL) */
server.unixtime = time(NULL);
/* We have just 21 bits per object for LRU information.
/* We have just 22 bits per object for LRU information.
* So we use an (eventually wrapping) LRU clock with minutes resolution.
* 2^22 minutes are more than 7 years.
*
* When we need to select what object to swap, we compute the minimum
* time distance between the current lruclock and the object last access
* lruclock info. Even if clocks will wrap on overflow, there is
* the interesting property that we are sure that at least
* ABS(A-B) minutes passed between current time and timestamp B.
*
* This is not precise but we don't need at all precision, but just
* something statistically reasonable.
* Note that even if this will wrap after 7 years it's not a problem,
* everything will still work but just some object will appear younger
* to Redis :)
*/
server.lruclock = (time(NULL)/60)&((1<<21)-1);
server.lruclock = (time(NULL)/60) & REDIS_LRU_CLOCK_MAX;
/* We received a SIGTERM, shutting down here in a safe way, as it is
* not ok doing so inside the signal handler. */
@ -1165,6 +1161,7 @@ sds genRedisInfoString(void) {
"process_id:%ld\r\n"
"uptime_in_seconds:%ld\r\n"
"uptime_in_days:%ld\r\n"
"lru_clock:%ld\r\n"
"used_cpu_sys:%.2f\r\n"
"used_cpu_user:%.2f\r\n"
"used_cpu_sys_childrens:%.2f\r\n"
@ -1196,6 +1193,7 @@ sds genRedisInfoString(void) {
(long) getpid(),
uptime,
uptime/(3600*24),
(unsigned long) server.lruclock,
(float)self_ru.ru_utime.tv_sec+(float)self_ru.ru_utime.tv_usec/1000000,
(float)self_ru.ru_stime.tv_sec+(float)self_ru.ru_stime.tv_usec/1000000,
(float)c_ru.ru_utime.tv_sec+(float)c_ru.ru_utime.tv_usec/1000000,