Great progress, guys! It’s impressive to see all the enhancements - more types, more aggregate functions, cross-node DML, resharding, and reliability-focused connection pooling and more. Very cool! These were really hard problems and took multiple years to build at Citus. Kudos to the shipping velocity.
codegeek
Stupid question but does this shard the database as well or do we shard manually and then setup the configuration accordingly ?
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cuu508
Some HTTP proxies can do retries -- if a connection to one backend fails, it is retried on a different backend. Can PgDog (or PgBouncer, or any other tool) do something similar -- if there's a "database server shutting down" error or a connection reset, retry it on another backend?
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mijoharas
Happy pgdog user here, I can recommend it from a user perspective as a connection pooler to anyone checking this out (we're also running tests and positive about sharding, but haven't run it in prod yet, so I can't 100% vouch for it on that, but that's where we're headed.)
@Lev, how is the 2pc coming along? I think it was pretty new when I last checked, and I haven't looked into it much since then. Is it feeling pretty solid now?
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mosselman
I see the word 'replication' mentioned quite a few times. Is this managed by pgdog? Would I be able to replace other logical replication setups with pgdog to create a High Availability cluster?
Do you have any write up on how to do this?
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jackfischer
Congrats guys! Curious how the read write splitting is reliable in practice due to replication lag. Do you need to run the underlying cluster with synchronous replication?
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octoclaw
The cross-shard aggregate rewriting is really nice. Transparently injecting count() for average calculations sounds straightforward but there are so many edge cases once you add GROUP BY, HAVING, subqueries, etc.
Curious about latency overhead for the common case. On a direct-to-shard read where no rewriting happens, what's the added latency from going through PgDog vs connecting to Postgres directly? Sub-millisecond?
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noleary
> If you build apps with a lot of traffic, you know the first thing to break is the database.
Just out of curiosity, what kinds of high-traffic apps have been most interested in using PgDog? I see you guys have Coinbase and Ramp logos on your homepage -- seems like fintech is a fit?
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array_loader
(apologies for new account - NDA applies to the specifics)
Nice surprise to see this here today. I was working on a deployment just last week.
Unfortunately for me, I found that it crashed when doing a very specific bulk load (COPY FORMAT BINARY with array columns inside a transaction). The process loads around 200MB of array columns (in the region of 10K rows) into a variety of tables. Very early in the COPY process PgDog crashes with :
"pgdog router error: failed to fill whole buffer"
So it appears something is not quite right for my specific use case (COPY with array columns). I'm not familiar enough with Rust but the failed to fill whole buffer seemed to come from Rust (rather than PgDog) based on what little I could find with searches.
I was very disappointed as it looked much simpler to get set up and running that PgPool-II (which I have had to revert to as my backup plan - I'm finding it more difficult to configured, but it does cope with the COPY command without issues).
I would have preferred to stick with PgDog.
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[deleted]
I_am_tiberius
I really hope to use the sharding feature one day.
Great progress, guys! It’s impressive to see all the enhancements - more types, more aggregate functions, cross-node DML, resharding, and reliability-focused connection pooling and more. Very cool! These were really hard problems and took multiple years to build at Citus. Kudos to the shipping velocity.
Stupid question but does this shard the database as well or do we shard manually and then setup the configuration accordingly ?
Some HTTP proxies can do retries -- if a connection to one backend fails, it is retried on a different backend. Can PgDog (or PgBouncer, or any other tool) do something similar -- if there's a "database server shutting down" error or a connection reset, retry it on another backend?
Happy pgdog user here, I can recommend it from a user perspective as a connection pooler to anyone checking this out (we're also running tests and positive about sharding, but haven't run it in prod yet, so I can't 100% vouch for it on that, but that's where we're headed.)
@Lev, how is the 2pc coming along? I think it was pretty new when I last checked, and I haven't looked into it much since then. Is it feeling pretty solid now?
I see the word 'replication' mentioned quite a few times. Is this managed by pgdog? Would I be able to replace other logical replication setups with pgdog to create a High Availability cluster?
Do you have any write up on how to do this?
Congrats guys! Curious how the read write splitting is reliable in practice due to replication lag. Do you need to run the underlying cluster with synchronous replication?
The cross-shard aggregate rewriting is really nice. Transparently injecting count() for average calculations sounds straightforward but there are so many edge cases once you add GROUP BY, HAVING, subqueries, etc.
Curious about latency overhead for the common case. On a direct-to-shard read where no rewriting happens, what's the added latency from going through PgDog vs connecting to Postgres directly? Sub-millisecond?
> If you build apps with a lot of traffic, you know the first thing to break is the database.
Just out of curiosity, what kinds of high-traffic apps have been most interested in using PgDog? I see you guys have Coinbase and Ramp logos on your homepage -- seems like fintech is a fit?
(apologies for new account - NDA applies to the specifics)
Nice surprise to see this here today. I was working on a deployment just last week.
Unfortunately for me, I found that it crashed when doing a very specific bulk load (COPY FORMAT BINARY with array columns inside a transaction). The process loads around 200MB of array columns (in the region of 10K rows) into a variety of tables. Very early in the COPY process PgDog crashes with :
"pgdog router error: failed to fill whole buffer"
So it appears something is not quite right for my specific use case (COPY with array columns). I'm not familiar enough with Rust but the failed to fill whole buffer seemed to come from Rust (rather than PgDog) based on what little I could find with searches.
I was very disappointed as it looked much simpler to get set up and running that PgPool-II (which I have had to revert to as my backup plan - I'm finding it more difficult to configured, but it does cope with the COPY command without issues).
I would have preferred to stick with PgDog.
I really hope to use the sharding feature one day.
Looks great - I'd love to include it in https://postgresisenough.dev (just put in a PR: https://github.com/agoodway/postgresisenough?tab=readme-ov-f...)