In-memory PostgreSQL database

#11

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#12

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#13

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#14

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#15

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#16

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#17

Ben Finney wrote:

Quote:

What options are there for creating and connnecting to a PostgreSQL
database that exists only in memory, similar to the same thing in
SQLite (and, I believe, MySQL)?

I don't think you would gain anything by keeping the DB in RAM with
postgres, because it's CPU-bound if there is little data.

If the test DB fits in RAM, this means Postgres already leverages the
memory as cache (if configured properly)

In my current application, I truncate and refill all the tables after
each of the 500 test.

I tried creating a tablespace in ramdisk, and had no performance
improvement at all.

#18

Laurenz Albe wrote:

Quote:

I am very surprised that you even consider running unit tests with
anything else than the database you want to use in production. Doesn't
that take away much of the benefits of unit testing?

Not if the DB schema has been evolved with "emergent design" and makes
no use of triggers, stored procedures, advanced check constraints... if
you design an app like some of the youngsters do, the only difference
between sqlite and postgres is that the latter has better support for
unicode ;-)

#19

Laurenz Albe wrote:

Quote:

I am very surprised that you even consider running unit tests with
anything else than the database you want to use in production. Doesn't
that take away much of the benefits of unit testing?

Not if the DB schema has been evolved with "emergent design" and makes
no use of triggers, stored procedures, advanced check constraints... if
you design an app like some of the youngsters do, the only difference
between sqlite and postgres is that the latter has better support for
unicode ;-)

#20

Laurenz Albe wrote:

Quote:

I am very surprised that you even consider running unit tests with
anything else than the database you want to use in production. Doesn't
that take away much of the benefits of unit testing?

Not if the DB schema has been evolved with "emergent design" and makes
no use of triggers, stored procedures, advanced check constraints... if
you design an app like some of the youngsters do, the only difference
between sqlite and postgres is that the latter has better support for
unicode ;-)