Proboscis 0.1 Release

James William Pye x at jwp.name
Sun Sep 25 11:00:25 CEST 2005


This is the first release announcement for Proboscis[1], the PQueue
based Green Trunk implementation. It is a PostgreSQL driver/interface
for Python. Another one? Well, yes and no. Proboscis is not libpq
based, nor does it primarily produce a DB-API 2.0 interface(0.2 may
include a layer for DB-API 2.0 users).

The release news item can be found here[2].

This frontend features, in no particular order, the following:
 * Pure Python
 * Green Trunk interface
 * Thread safety
 * Windows support
 * Basic SSL support
 * COPY TO/FROM support
 * Protocol level prepared statements and cursors(Portals)
 * Demand based cursor activity
 * query and procedure methods (see Green Trunk documentation)
 * bytea transparency (hint: no need to escape when using parameters)
 * Wire Tap (asynchronous notifications)
 * Automatic client encoding/decoding

Pure Python? It must be slow, no? Well, first, there is an optional C
extension module to provide an optimization in one sensitive area, so it's
not necessarily pure Python. As 1.0 approaches, other sensitive areas may be
optimized as well.

So how slow or fast is it? The following are some simple trials:
(The server and the client are on the same machine)

Copying,

COPY FROM Summary,
 copied tuples: 50000
 copied bytes: 2882981
 duration: 2.186987
 average tuple size(bytes): 57.000000
 average KB per second: 1287.159045
 average tuples per second: 22862.505244

COPY TO Summary,
 copied tuples: 50000
 duration: 2.299819
 average KB per second: 1224.009372
 average tuples per second: 21740.841414

(Warning: Without the C extension module, COPY TO's TPS will be cut in half)

Querying,

INSERT Summary,
 inserted tuples: 1000
 total time: 1.903957
 average tuples per second: 525.221976

(Note: Mass INSERT will likely be ~2-3x faster in version 0.2)

SELECT Summary,
 looped: 51
 read tuples: 1000
 looptime: 0.323199
 time reading tuples: 0.322262
 loop overhead: 0.000937
 average tuples per second: 3103.064739

(Warning: Without the C extension module, SELECT will lose 1000TPS)

While it is unlikely that these speeds will be seen in practice, it does give
one an idea as to what this interface can do with simple data.

For the quickest way to get started, see the Frontend sections of the Quick
Start page[4]. For further help, sign-up and post questions to the mailing
list[5].

[1] http://python.projects.postgresql.org/project/fe.html
[2] http://pgfoundry.org/forum/forum.php?forum_id=522
[3] http://pgfoundry.org/frs/?group_id=1000094&release_id=315
[4] http://python.projects.postgresql.org/quick.html
[5] http://lists.pgfoundry.org/mailman/listinfo/python-general


More information about the Python-announce-list mailing list