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I think its that its an in memory database, optimised for memory as opposed to disk. The SQL to C++ seems a bit of a confusion to me, I guess it means it has a

I think its that its an in memory database, optimised for memory as opposed to disk. The SQL to C++ seems a bit of a confusion to me, I guess it means it has a JIT SQL compiler to optimise the query to native opcodes. Meh. But the in memory and mysql wire compatibility are big wins.

chris_wot 14y ago
I don't believe this is the case - it's not an in-memory database. Even if it is (and I can't see anything on their developer website) then if it's ACID compliant, like they say, then it will have to be writing to the disk at some point - at the very least it will need a transaction log. Otherwise, it's not really usable for anything you need to persist to long term storage!
- al_james 14y ago
  Yes, its not clear on their site, but the gigaom article states: "As its name implies, MemSQL achieves its fast performance in part by keeping data in memory". Yes, it does write to disk (append only logging I think) but my point was, that if you are keeping ALL your data in memory, you can optimise the storage for fast queries, as opposed to a hybrid / paged memory and disk system.
  - chris_wot 14y ago
    Oops, sorry - I'm wrong. Actually, according to their documentation: "By default, MemSQL runs with full durability enabled: transactions are committed to disk as a log and later compressed into full-database snapshots. The snapshot and log files are stored in the datadir directory configured in memsql.cnf. When MemSQL is restarted, it will recover itself into the state it was in before the shutdown, by reading the snapshot and log files in datadir" [1] I missed that piece of documentation on their website. I think they could do better to explain better the advantages and how their technology works. Their product overview doesn't really tell you much of anything, except that they have an enhanced query parser. [2] 1. http://developers.memsql.com/docs/1b/durability.html http://developers.memsql.com/docs/1b/durability.html 2. http://developers.memsql.com/ http://developers.memsql.com/
- deleted 14y ago
  [deleted]
zwischenzug 14y ago
Over what? The big iron DB I use is to all intents and purposes in memory in any case. The only Input requirement is to pull the data in at some point (which can be forced) and the Output requirement is to write to a logical log (which we buffer in any case). It flies.
ericfrenkiel 14y ago
yes, memsql is an in-memory database. the big innovation here is that we're literally hardwiring the SQL into the server and matching queries to those compiled query templates. Since we work in memory, you see a huge perf boost with code generation because there are no lags with disk.

chris_wot 14y ago

I don't believe this is the case - it's not an in-memory database. Even if it is (and I can't see anything on their developer website) then if it's ACID compliant, like they say, then it will have to be writing to the disk at some point - at the very least it will need a transaction log. Otherwise, it's not really usable for anything you need to persist to long term storage!

al_james 14y ago
Yes, its not clear on their site, but the gigaom article states: "As its name implies, MemSQL achieves its fast performance in part by keeping data in memory". Yes, it does write to disk (append only logging I think) but my point was, that if you are keeping ALL your data in memory, you can optimise the storage for fast queries, as opposed to a hybrid / paged memory and disk system.
- chris_wot 14y ago
  Oops, sorry - I'm wrong. Actually, according to their documentation: "By default, MemSQL runs with full durability enabled: transactions are committed to disk as a log and later compressed into full-database snapshots. The snapshot and log files are stored in the datadir directory configured in memsql.cnf. When MemSQL is restarted, it will recover itself into the state it was in before the shutdown, by reading the snapshot and log files in datadir" [1] I missed that piece of documentation on their website. I think they could do better to explain better the advantages and how their technology works. Their product overview doesn't really tell you much of anything, except that they have an enhanced query parser. [2] 1. http://developers.memsql.com/docs/1b/durability.html http://developers.memsql.com/docs/1b/durability.html 2. http://developers.memsql.com/ http://developers.memsql.com/
deleted 14y ago
[deleted]

zwischenzug 14y ago

Over what? The big iron DB I use is to all intents and purposes in memory in any case. The only Input requirement is to pull the data in at some point (which can be forced) and the Output requirement is to write to a logical log (which we buffer in any case). It flies.

ericfrenkiel 14y ago

yes, memsql is an in-memory database. the big innovation here is that we're literally hardwiring the SQL into the server and matching queries to those compiled query templates. Since we work in memory, you see a huge perf boost with code generation because there are no lags with disk.