mirror of https://mirror.osredm.com/root/redis.git
7b9e960690
## 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.
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| .. | ||
| aof-multi-part.tcl | ||
| aof-race.tcl | ||
| aof.tcl | ||
| block-repl.tcl | ||
| convert-ziplist-hash-on-load.tcl | ||
| convert-ziplist-zset-on-load.tcl | ||
| convert-zipmap-hash-on-load.tcl | ||
| corrupt-dump-fuzzer.tcl | ||
| corrupt-dump.tcl | ||
| dismiss-mem.tcl | ||
| failover.tcl | ||
| logging.tcl | ||
| psync2-master-restart.tcl | ||
| psync2-pingoff.tcl | ||
| psync2-reg.tcl | ||
| psync2.tcl | ||
| rdb.tcl | ||
| redis-benchmark.tcl | ||
| redis-cli.tcl | ||
| replication-2.tcl | ||
| replication-3.tcl | ||
| replication-4.tcl | ||
| replication-buffer.tcl | ||
| replication-psync.tcl | ||
| replication.tcl | ||
| shutdown.tcl | ||