Redis/redis
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Hash Field Expiration (#13303)

Browse Source 
## Background

This PR introduces support for field-level expiration in Redis hashes. Previously, Redis supported expiration only at the key level, but this enhancement allows setting expiration times for individual fields within a hash.

## New commands
* HEXPIRE
* HEXPIREAT
* HEXPIRETIME
* HPERSIST
* HPEXPIRE
* HPEXPIREAT
* HPEXPIRETIME
* HPTTL
* HTTL

## Short example
from @moticless
```sh
127.0.0.1:6379>  hset myhash f1 v1 f2 v2 f3 v3                                                   
(integer) 3
127.0.0.1:6379>  hpexpire myhash 10000 NX fields 2 f2 f3                                         
1) (integer) 1
2) (integer) 1
127.0.0.1:6379>  hpttl myhash fields 3 f1 f2 f3                                                                                                                                                                         
1) (integer) -1
2) (integer) 9997
3) (integer) 9997
127.0.0.1:6379>  hgetall myhash  
1) "f3"
2) "v3"
3) "f2"
4) "v2"
5) "f1"
6) "v1"

... after 10 seconds ...

127.0.0.1:6379>  hgetall myhash  
1) "f1"
2) "v1"
127.0.0.1:6379>
```

## Expiration strategy
1. Integrate active
    Redis periodically performs active expiration and deletion of hash keys that contain expired fields, with a maximum attempt limit.
3. Lazy expiration
    When a client touches fields within a hash, Redis checks if the fields are expired. If a field is expired, it will be deleted. However, we do not delete expired fields during a traversal, we implicitly skip over them.

## RDB changes
Add two new rdb type s`RDB_TYPE_HASH_METADATA` and `RDB_TYPE_HASH_LISTPACK_EX`.

## Notification
1. Add `hpersist` notification for `HPERSIST` command.
5. Add `hexpire` notification for `HEXPIRE`, `HEXPIREAT`, `HPEXPIRE` and `HPEXPIREAT` commands.

## Internal
1. Add new data structure `ebuckets`, which is used to store TTL and keys, enabling quick retrieval of keys based on TTL.
2. Add new data structure `mstr` like sds, which is used to store a string with TTL.

This work was done by @moticless, @tezc, @ronen-kalish, @sundb, I just release it.
This commit is contained in:
debing.sun
2024-05-30 15:26:19 +08:00
committed by GitHub
parent 2d1bb42cba f0389f2823
commit 7b9e960690
53 changed files with 10243 additions and 573 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/object.c
+12 -16
View File
@@ -333,17 +333,7 @@ void freeZsetObject(robj *o) {
}
void freeHashObject(robj *o) {
switch (o->encoding) {
case OBJ_ENCODING_HT:
dictRelease((dict*) o->ptr);
break;
case OBJ_ENCODING_LISTPACK:
lpFree(o->ptr);
break;
default:
serverPanic("Unknown hash encoding type");
break;
}
hashTypeFree(o);
}
void freeModuleObject(robj *o) {
@@ -502,6 +492,9 @@ void dismissHashObject(robj *o, size_t size_hint) {
dismissMemory(d->ht_table[1], DICTHT_SIZE(d->ht_size_exp[1])*sizeof(dictEntry*));
} else if (o->encoding == OBJ_ENCODING_LISTPACK) {
dismissMemory(o->ptr, lpBytes((unsigned char*)o->ptr));
} else if (o->encoding == OBJ_ENCODING_LISTPACK_EX) {
listpackEx *lpt = o->ptr;
dismissMemory(lpt->lp, lpBytes((unsigned char*)lpt->lp));
} else {
serverPanic("Unknown hash encoding type");
}
@@ -939,6 +932,7 @@ char *strEncoding(int encoding) {
case OBJ_ENCODING_HT: return "hashtable";
case OBJ_ENCODING_QUICKLIST: return "quicklist";
case OBJ_ENCODING_LISTPACK: return "listpack";
case OBJ_ENCODING_LISTPACK_EX: return "listpackex";
case OBJ_ENCODING_INTSET: return "intset";
case OBJ_ENCODING_SKIPLIST: return "skiplist";
case OBJ_ENCODING_EMBSTR: return "embstr";
@@ -979,7 +973,6 @@ size_t streamRadixTreeMemoryUsage(rax *rax) {
* are checked and averaged to estimate the total size. */
#define OBJ_COMPUTE_SIZE_DEF_SAMPLES 5 /* Default sample size. */
size_t objectComputeSize(robj *key, robj *o, size_t sample_size, int dbid) {
sds ele, ele2;
dict *d;
dictIterator *di;
struct dictEntry *de;
@@ -1016,7 +1009,7 @@ size_t objectComputeSize(robj *key, robj *o, size_t sample_size, int dbid) {
di = dictGetIterator(d);
asize = sizeof(*o)+sizeof(dict)+(sizeof(struct dictEntry*)*dictBuckets(d));
while((de = dictNext(di)) != NULL && samples < sample_size) {
ele = dictGetKey(de);
sds ele = dictGetKey(de);
elesize += dictEntryMemUsage() + sdsZmallocSize(ele);
samples++;
}
@@ -1052,14 +1045,17 @@ size_t objectComputeSize(robj *key, robj *o, size_t sample_size, int dbid) {
} else if (o->type == OBJ_HASH) {
if (o->encoding == OBJ_ENCODING_LISTPACK) {
asize = sizeof(*o)+zmalloc_size(o->ptr);
} else if (o->encoding == OBJ_ENCODING_LISTPACK_EX) {
listpackEx *lpt = o->ptr;
asize = sizeof(*o) + zmalloc_size(lpt) + zmalloc_size(lpt->lp);
} else if (o->encoding == OBJ_ENCODING_HT) {
d = o->ptr;
di = dictGetIterator(d);
asize = sizeof(*o)+sizeof(dict)+(sizeof(struct dictEntry*)*dictBuckets(d));
while((de = dictNext(di)) != NULL && samples < sample_size) {
ele = dictGetKey(de);
ele2 = dictGetVal(de);
elesize += sdsZmallocSize(ele) + sdsZmallocSize(ele2);
hfield ele = dictGetKey(de);
sds ele2 = dictGetVal(de);
elesize += hfieldZmallocSize(ele) + sdsZmallocSize(ele2);
elesize += dictEntryMemUsage();
samples++;
}