TODO cahnges

[redis.git] / TODO

diff --git a/TODO b/TODO
index 98241884042d10ab7ffe40c2f9b756d1e9e072e2..853b5ed912e05aa66e932e07e03cf09214d9437e 100644 (file)
--- a/TODO
+++ b/TODO
@@ -1,30 +1,26 @@
 Redis TODO and Roadmap
 
 Redis TODO and Roadmap
 

-VERSION 1.1 TODO (Zsets, Integer encoding, Append only journal)
-===============================================================
-
-Most of the features already implemented for this release. The following is a list of the missing things in order to release the first beta tar.gz:
-
-* For now only the last argument gets integer encoded, so make sure that: 1) every multi bulk command implemented will have the last arg that is indeed a value, and not used otherwise. 2) to explicitly call the function to encode the object in MSET and other commands where there are multiple "values".
-* Man pages for SRANDMEMBER, missing Z-commands, ...
-* Use strcoll() to compare objects in sorted sets, like it already happens for SORT.
-* Write docs for the "STORE" operaiton of SORT. Link to the article about SORT by written by defunkt.
-* Append only mode: testing and a command to rebuild the log from scratch.
-* ZRANGEBYSCORE test, ZRANGEBYSCORE LIMIT option.
-* Sorted sets infinity tests.
-
-VERSION 1.2 TODO (Hash type)
+VERSION 1.4 TODO (Hash type)

 ============================
 
 ============================
 

-* Hashes (HSET, HGET, HEXISTS, HLEN, ...).
-* An utility able to export an .rdb file into a text-only JSON dump, we can't live anymore without such a tool. Probably an extension to redis-cli.
+* BRPOPLPUSH
+* List ops like L/RPUSH L/RPOP should return the new list length.
+* Save dataset / fsync() on SIGTERM
+* MULTI/EXEC should support the "EXEC FSYNC" form?
+* BLPOP & C. tests (write a non blocking Tcl client as first step)

 
 

-VERSION 1.3 TODO (Virtual memory)
-=================================
+Virtual Memory sub-TODO:
+* Check if the page selection algorithm is working well
+* Divide swappability of objects by refcount
+* it should be possible to give the vm-max-memory option in megabyte, gigabyte, ..., just using 2GB, 100MB, and so forth.
+* Try to understand what can be moved into I/O threads that currently is instead handled by the main thread. For instance swapping file table scannig to find contiguous page could be a potential candidate (but I'm not convinced it's a good idea, better to improve the algorithm, for instance double the fast forward at every step?).
+* Possibly decrRefCount() against swapped objects can be moved into I/O threads, as it's a slow operation against million elements list, and in general consumes CPU time that can be consumed by other threads (and cores).
+* EXISTS should avoid loading the object if possible without too make the code too specialized.
+* vm-min-age <seconds> option

 
 

-* Redis Virtual Memory for datasets bigger than RAM (http://groups.google.com/group/redis-db/msg/752997c7b38553cd)
+* Hashes (GET/SET/DEL/INCRBY/EXISTS/FIELDS/LEN/MSET/MGET). Special encoding for hashes with < N keys.

 
 

-VERSION 1.4 TODO (Fault tollerant sharding)
+VERSION 2.2 TODO (Fault tolerant sharding)

 ===========================================
 
 * Redis-cluster, a fast intermediate layer (proxy) that implements consistent hashing and fault tollerant nodes handling.
 ===========================================
 
 * Redis-cluster, a fast intermediate layer (proxy) that implements consistent hashing and fault tollerant nodes handling.


@@ -33,7 +29,7 @@ Interesting readings about this:
 
     - http://ayende.com/Blog/archive/2009/04/06/designing-rhino-dht-a-fault-tolerant-dynamically-distributed-hash.aspx
 
 
     - http://ayende.com/Blog/archive/2009/04/06/designing-rhino-dht-a-fault-tolerant-dynamically-distributed-hash.aspx
 

-VERSION 1.5 TODO (Optimizations and latency)
+VERSION 2.4 TODO (Optimizations and latency)

 ============================================
 
 * Lower the CPU usage.
 ============================================
 
 * Lower the CPU usage.


@@ -41,12 +37,41 @@ VERSION 1.5 TODO (Optimizations and latency)
 * Use epool and alike to rewrite ae.c for Linux and other platforms suppporting fater-than-select() mutiplexing APIs.
 * Implement an UDP interface for low-latency GET/SET operations.
 
 * Use epool and alike to rewrite ae.c for Linux and other platforms suppporting fater-than-select() mutiplexing APIs.
 * Implement an UDP interface for low-latency GET/SET operations.
 

-SHORT/LONG TERM RANDOM TODO ITEMS
-=================================
+OTHER IMPORTANT THINGS THAT WILL BE ADDED BUT I'M NOT SURE WHEN
+===============================================================
+
+BIG ONES:
+
+* 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)
+* ZRANK: http://docs.google.com/viewer?a=v&q=cache:tCQaP3ZeN4YJ:courses.csail.mit.edu/6.046/spring04/handouts/ps5-sol.pdf+skip+list+rank+operation+augmented&hl=en&pid=bl&srcid=ADGEEShXuNjTcZyXw_1cq9OaWpSXy3PprjXqVzmM-LE0ETFznLyrDXJKQ_mBPNT10R8ErkoiXD9JbMw_FaoHmOA4yoGVrA7tZWiy393JwfCwuewuP93sjbkzZ_gnEp83jYhPYjThaIzw&sig=AHIEtbRF0GkYCdYRFtTJBE69senXZwFY0w
+
+SMALL ONES:
+
+* 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.
+
+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.
- * LOCK / TRYLOCK / UNLOCK as described many times in the google group
- * Replication automated tests
- * BYTEDARRAY type
- * zmalloc() should avoid to add a private header for archs where there is some other kind of libc-specific way to get the size of a malloced block.
+* Move dict.c from hash table to skip list, in order to avoid the blocking resize operation needed for the hash table.
+* FORK command (fork()s executing the commands received by the current
+  client in the new process). Hint: large SORTs can use more cores,
+  copy-on-write will avoid memory problems.
+* DUP command? DUP srckey dstkey, creates an exact clone of srckey value in dstkey.
+* 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.
+* LOCK / TRYLOCK / UNLOCK as described many times in the google group
+* Replication automated tests
+* 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.
+* zmalloc() should avoid to add a private header for archs where there is some other kind of libc-specific way to get the size of a malloced block. Already done for Mac OS X.
+* Read-only mode.
+* Pattern-matching replication.
+* Add an option to relax the delete-expiring-keys-on-write semantic *denying* replication and AOF when this is on? Can be handy sometimes, when using Redis for non persistent state, but can create problems. For instance should rename and move also "move" the timeouts? How does this affect other commands?
+* Multiple BY in SORT.