[redis.git] / TODO

Redis TODO and Roadmap
----------------------

VERSION 2.2 TODO (Optimizations and latency)
============================================

* SETNX when failing should not affect WATCH
* Support for syslog(3).
* Document ZCOUNT.
* Change the implementation of ZCOUNT to use the augmented skiplist in order to be much faster.
* Add an explicit test for MULTI/EXEC reloaded in the AOF.

VM TODO
=======

* Use multiple open FDs against the VM file, one for thread.
* Check what happens performance-wise if instead of creating threads again and again the same threads are reused forever. Note: this requires a way to disable this clients in the child, but waiting for empty new jobs queue can be enough.

STRING COMMANDS
===============

* Implement STRLEN, PEEK, POKE, SETBIT, GETBIT

OTHER IMPORTANT THINGS THAT WILL BE ADDED BUT I'M NOT SURE WHEN
===============================================================

BIG ONES:

* BRPOPLPUSH
* Specially encoded memory-saving integer sets.
* A command to export a JSON dump (there should be mostly working patch needing major reworking).
* Specially encoded sets of integers (this includes a big refactoring providing an higher level layer for Sets manipulation)

SMALL ONES:

* If sizeof(double) == sizeof(void*) we could store the double value of sorted sets directly in place of the pointer instead of allocating it in the heap.
* Delete on writes against expire policy should only happen after argument parsing for commands doing their own arg parsing stuff.
* Give errors when incrementing a key that does not look like an integer, when providing as a sorted set score something can't be parsed as a double, and so forth.
* MSADD (n keys) (n values). See this thread in the Redis google group: http://groups.google.com/group/redis-db/browse_thread/thread/e766d84eb375cd41
* Don't save empty lists / sets / zsets on disk with snapshotting.
* Remove keys when a list / set / zset reaches length of 0.
* An option to exec a command slave-side if the master connection is lost: even cooler: if the script returns "0" the slave elects itself as master, otherwise continue trying to reconnect.
* PING the master from time to time to check if it's gone.

THE "MAYBE" TODO LIST: things that may or may not get implemented
=================================================================

Most of this can be seen just as proposals, the fact they are in this list
it's not a guarantee they'll ever get implemented ;)

* SORT: Don't copy the list into a vector when BY argument is constant.
* Write the hash table size of every db in the dump, so that Redis can resize the hash table just one time when loading a big DB.
* Byte Array type (BA prefixed commands): BASETBIT BAGETBIT BASETU8 U16 U32 U64 S8 S16 S32 S64, ability to atomically INCRBY all the base types. BARANGE to get a range of bytes as a bulk value, BASETRANGE to set a range of bytes.
* Read-only mode.
* Kill the delete-on-write behavior of expires, replicating DELs
* Multiple BY in SORT.

KNOWN BUGS
==========

* LRANGE and other commands are using 32 bit integers for ranges, and overflows are not detected. So LRANGE mylist 0 23498204823094823904823904 will have random effects.
Commit	Line	Data
f284d963	1	Redis TODO and Roadmap
469c4e45	2	----------------------
f284d963	3
469c4e45	4	VERSION 2.2 TODO (Optimizations and latency)
	5	============================================
	6
5b4bff9c	7	* SETNX when failing should not affect WATCH
356f9239	8	* Support for syslog(3).
5b4bff9c	9	* Document ZCOUNT.
32a66513	10	* Change the implementation of ZCOUNT to use the augmented skiplist in order to be much faster.
d06a5b23	11	* Add an explicit test for MULTI/EXEC reloaded in the AOF.
f6b141c5	12
bb8716b6	13	VM TODO
	14	=======
	15
7c775e09	16	* Use multiple open FDs against the VM file, one for thread.
469c4e45	17	* Check what happens performance-wise if instead of creating threads again and again the same threads are reused forever. Note: this requires a way to disable this clients in the child, but waiting for empty new jobs queue can be enough.
bb8716b6	18
	19	STRING COMMANDS
	20	===============
	21
	22	* Implement STRLEN, PEEK, POKE, SETBIT, GETBIT
7d65b33d	23
3f477979	24	OTHER IMPORTANT THINGS THAT WILL BE ADDED BUT I'M NOT SURE WHEN
	25	===============================================================
	26
	27	BIG ONES:
	28
bb8716b6	29	* BRPOPLPUSH
3f477979	30	* Specially encoded memory-saving integer sets.
3f477979	31	* A command to export a JSON dump (there should be mostly working patch needing major reworking).
f0c138f6	32	* Specially encoded sets of integers (this includes a big refactoring providing an higher level layer for Sets manipulation)
3f477979	33
	34	SMALL ONES:
	35
ada386b2	36	* If sizeof(double) == sizeof(void*) we could store the double value of sorted sets directly in place of the pointer instead of allocating it in the heap.
978c2c94	37	* Delete on writes against expire policy should only happen after argument parsing for commands doing their own arg parsing stuff.
3f477979	38	* Give errors when incrementing a key that does not look like an integer, when providing as a sorted set score something can't be parsed as a double, and so forth.
25e52257	39	* MSADD (n keys) (n values). See this thread in the Redis google group: http://groups.google.com/group/redis-db/browse_thread/thread/e766d84eb375cd41
f0c138f6	40	* Don't save empty lists / sets / zsets on disk with snapshotting.
f0c138f6	41	* Remove keys when a list / set / zset reaches length of 0.
5921aa36	42	* An option to exec a command slave-side if the master connection is lost: even cooler: if the script returns "0" the slave elects itself as master, otherwise continue trying to reconnect.
3ea27d37	43	* PING the master from time to time to check if it's gone.
3f477979	44
f0c138f6	45	THE "MAYBE" TODO LIST: things that may or may not get implemented
f0c138f6	46	=================================================================
f6b141c5	47
0188805d	48	Most of this can be seen just as proposals, the fact they are in this list
	49	it's not a guarantee they'll ever get implemented ;)
	50
682ac724	51	* SORT: Don't copy the list into a vector when BY argument is constant.
682ac724	52	* Write the hash table size of every db in the dump, so that Redis can resize the hash table just one time when loading a big DB.
682ac724	53	* Byte Array type (BA prefixed commands): BASETBIT BAGETBIT BASETU8 U16 U32 U64 S8 S16 S32 S64, ability to atomically INCRBY all the base types. BARANGE to get a range of bytes as a bulk value, BASETRANGE to set a range of bytes.
682ac724	54	* Read-only mode.
bb8716b6	55	* Kill the delete-on-write behavior of expires, replicating DELs
f0c138f6	56	* Multiple BY in SORT.
cef34df0	57
	58	KNOWN BUGS
	59	==========
	60
	61	* LRANGE and other commands are using 32 bit integers for ranges, and overflows are not detected. So LRANGE mylist 0 23498204823094823904823904 will have random effects.