[redis.git] / TODO

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

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

* Support for syslog(3).
* 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.
* Command table -> hash table, with support for command renaming

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.

REDIS CLI TODO
==============

* Computer parsable output generation
* Memoize return values so that they can be used later as arguments, like $1
Commit	Line	Data
f284d963	1	Redis TODO and Roadmap
469c4e45	2	----------------------
f284d963	3
469c4e45	4	VERSION 2.2 TODO (Optimizations and latency)
	5	============================================
	6
356f9239	7	* Support for syslog(3).
32a66513	8	* Change the implementation of ZCOUNT to use the augmented skiplist in order to be much faster.
d06a5b23	9	* Add an explicit test for MULTI/EXEC reloaded in the AOF.
2cffe299	10	* Command table -> hash table, with support for command renaming
f6b141c5	11
bb8716b6	12	VM TODO
	13	=======
	14
7c775e09	15	* Use multiple open FDs against the VM file, one for thread.
469c4e45	16	* 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	17
	18	STRING COMMANDS
	19	===============
	20
	21	* Implement STRLEN, PEEK, POKE, SETBIT, GETBIT
7d65b33d	22
3f477979	23	OTHER IMPORTANT THINGS THAT WILL BE ADDED BUT I'M NOT SURE WHEN
	24	===============================================================
	25
	26	BIG ONES:
	27
bb8716b6	28	* BRPOPLPUSH
3f477979	29	* Specially encoded memory-saving integer sets.
3f477979	30	* A command to export a JSON dump (there should be mostly working patch needing major reworking).
f0c138f6	31	* Specially encoded sets of integers (this includes a big refactoring providing an higher level layer for Sets manipulation)
3f477979	32
	33	SMALL ONES:
	34
ada386b2	35	* 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	36	* Delete on writes against expire policy should only happen after argument parsing for commands doing their own arg parsing stuff.
3f477979	37	* 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	38	* 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	39	* Don't save empty lists / sets / zsets on disk with snapshotting.
f0c138f6	40	* Remove keys when a list / set / zset reaches length of 0.
5921aa36	41	* 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	42	* PING the master from time to time to check if it's gone.
3f477979	43
f0c138f6	44	THE "MAYBE" TODO LIST: things that may or may not get implemented
f0c138f6	45	=================================================================
f6b141c5	46
0188805d	47	Most of this can be seen just as proposals, the fact they are in this list
	48	it's not a guarantee they'll ever get implemented ;)
	49
682ac724	50	* SORT: Don't copy the list into a vector when BY argument is constant.
682ac724	51	* 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	52	* 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	53	* Read-only mode.
bb8716b6	54	* Kill the delete-on-write behavior of expires, replicating DELs
f0c138f6	55	* Multiple BY in SORT.
cef34df0	56
	57	KNOWN BUGS
	58	==========
	59
	60	* 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.
2cffe299	61
	62	REDIS CLI TODO
	63	==============
	64
	65	* Computer parsable output generation
	66	* Memoize return values so that they can be used later as arguments, like $1