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Add pljava messages.
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Bruce Momjian
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f7dfb1c606
@ -1101,3 +1101,703 @@ Let us cross over the river, and rest under the shade of the trees.
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From pgsql-jdbc-owner+M2545@postgresql.org Tue Dec 4 12:49:03 2001
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Tue, 4 Dec 2001 08:44:50 -0800
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Message-ID: <3C0CFD82.1030600@xythos.com>
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Date: Tue, 04 Dec 2001 08:44:50 -0800
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From: Barry Lind <barry@xythos.com>
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To: Laszlo Hornyak <hornyakl@freemail.hu>
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cc: pgsql-general@postgresql.org, pgsql-jdbc@postgresql.org
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Subject: Re: [JDBC] [GENERAL] java stored procedures
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References: <3C074DE4.9040905@freemail.hu> <3C0BE325.3020809@xythos.com> <3C0C937E.9000405@freemail.hu>
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Laszlo,
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I think it would help a lot if you could take a little time to write
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down what your planned architecture for a pljava would be. It then
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becomes much easier for myself and probably others reading these lists
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to make suggestions on ways to improve what you are planning (or
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possible problems with your strategy). Without knowing what exactly you
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are thinking of doing it is difficult to comment.
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But let me try throwing out a few thoughts about how I think this should
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be done.
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First question is how will the jvm be run? Since postgres is a
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multiprocess implementation (i.e. each connection has a separate process
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on the server) and since java is a multithreaded implementation (i.e.
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one process supporting multiple threads), what should the pljava
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implementation look like? I think there should be a single jvm process
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for the entire db server that each postgresql process connects to
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through sockets/rmi. It will be too expensive to create a new jvm
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process for each postgresql connection (expensive in both terms of
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memory and cpu, since the startup time for the jvm is significant and it
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requires a lot of memory).
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Having one jvm that all the postgres backend processes communicate with
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makes the whole feature much more complicated, but is necessary in my
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opinion.
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Then the question becomes how does the jvm process interact with the
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database since they are two different processes. You will need some
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sort of interprocess communication between the two to execute sql
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statements. This could be accomplished by using the existing jdbc
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driver. But the bigest problem here is getting the transaction
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semantics right. How does a sql statement being run by a java stored
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procedure get access to the same connection/transaction as the original
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client? What you don't want happening is that sql issued in a stored
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java procedure executes in a different transaction as the caller, what
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would rollback of the stored function call mean in that case?
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I am very interested in hearing what your plans are for pl/java. I
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think this is a very difficult project, but one that would be very
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useful and welcome.
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thanks,
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--Barry
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Laszlo Hornyak wrote:
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> Hi!
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>
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> I am such a lame in the licensing area. As much as I know, BSD license
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> is more free than GPL. I think it is too early to think about licensing,
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> but it`s ok, you won :), when it will be ready(or it will seem to get
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> closer to a working thing, currently it looks more like a interresting
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> test), I will ask you if you want to distribute it with Postgres, and if
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> you say yes, the license will be the same as Postgresql`s license.
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> Anyway is this neccessary when it is the part of the distribution?
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> Is this ok for you?
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>
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> thanks,
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> Laszlo Hornyak
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>
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> ps: still waiting for your ideas, suggestions, etc :) I am not memeber
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> of the mailing list, please write me dirrectly!
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>
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> Barry Lind wrote:
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>
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>> Laszlo,
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>>
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>> In my mind it would be more useful if this code was under the same
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>> license as the rest of postgresql. That way it could become part of
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>> the product as opposed to always being a separate component. (Just
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>> like plpgsql, pltcl and the other procedural languages).
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>>
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>> thanks,
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>> --Barry
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>>
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>>
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>
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>
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Date: Tue, 04 Dec 2001 20:18:52 +0100
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From: Laszlo Hornyak <hornyakl@freemail.hu>
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To: Barry Lind <barry@xythos.com>
|
||||
cc: pgsql-general@postgresql.org, pgsql-jdbc@postgresql.org
|
||||
Subject: Re: [JDBC] [GENERAL] java stored procedures
|
||||
References: <3C074DE4.9040905@freemail.hu> <3C0BE325.3020809@xythos.com> <3C0C937E.9000405@freemail.hu> <3C0CFD82.1030600@xythos.com>
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Status: OR
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Hi!
|
||||
|
||||
Barry Lind wrote:
|
||||
|
||||
> Laszlo,
|
||||
>
|
||||
> I think it would help a lot if you could take a little time to write
|
||||
> down what your planned architecture for a pljava would be. It then
|
||||
> becomes much easier for myself and probably others reading these lists
|
||||
> to make suggestions on ways to improve what you are planning (or
|
||||
> possible problems with your strategy). Without knowing what exactly
|
||||
> you are thinking of doing it is difficult to comment.
|
||||
|
||||
>
|
||||
>
|
||||
> But let me try throwing out a few thoughts about how I think this
|
||||
> should be done.
|
||||
>
|
||||
> First question is how will the jvm be run? Since postgres is a
|
||||
> multiprocess implementation (i.e. each connection has a separate
|
||||
> process on the server) and since java is a multithreaded
|
||||
> implementation (i.e. one process supporting multiple threads), what
|
||||
> should the pljava implementation look like? I think there should be a
|
||||
> single jvm process for the entire db server that each postgresql
|
||||
> process connects to through sockets/rmi. It will be too expensive to
|
||||
> create a new jvm process for each postgresql connection (expensive in
|
||||
> both terms of memory and cpu, since the startup time for the jvm is
|
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> significant and it requires a lot of memory).
|
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I absolutely agree. OK, it`s done.
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So, a late-night-brainstorming here:
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What I would like to see in PL/JAVA is the object oriented features,
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that makes postgresql nice. Creating a new table creates a new class in
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the java side too. Instantiating an object of the newly created class
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inserts a row into the table. In postgresql tables can be inherited, and
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this could be easyly done by pl/java too. I think this would look nice.
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But this is not the main feature. Why I would like to see a nice java
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procedural language inside postgres is java`s advanced communication
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features (I mean CORBA, jdbc, other protocols). This is the sugar in the
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caffe.
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I am very far from features like this.
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PL/JAVA now:
|
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-there is a separate process running java (kaffe). this process creates
|
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a sys v message queue, that holds requests. almost forgot, a shared
|
||||
memory segment too. I didn`t find better way to tell postgres the
|
||||
informations about the java process.
|
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-the java request_handler function on the server side attaches to the
|
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shared memory, reads the key of the message queue., attaches to it,
|
||||
sends the data of the function, and a signal for the pl/java. after, it
|
||||
is waiting for a signal from the java thread.
|
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-when java thread receives the signal, it reads the message(s) from the
|
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queue, and starts some actions. When done it tells postgres with a
|
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signal that it is ready, and it can come for its results. This will be
|
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rewritten see below problems.
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-And postgres is runing, while java is waiting for postgres to say
|
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something.
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|
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Threading on the java process side is not done yet, ok, it is not that
|
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hard, I will write it, if it will be realy neccessary.
|
||||
|
||||
The problems, for now:
|
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I had a very simple system, that passed a very limited scale of argument
|
||||
types, with a very limited quantity of parameters (int, varchar, bool).
|
||||
Postgres has limits for the argument count too, but not for types. It
|
||||
had too much limits, so I am working (or to tell the truth now only
|
||||
thinking) on a new type handling that fits the felxibility of
|
||||
Postgresql`s type flexibility. For this I will have to learn a lot about
|
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Postgres`s type system. This will be my program this weekend. :)
|
||||
|
||||
thanks,
|
||||
Laszlo Hornyak
|
||||
|
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Date: Tue, 04 Dec 2001 17:34:21 -0800
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From: Barry Lind <barry@xythos.com>
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To: hornyakl@users.sourceforge.net
|
||||
cc: pgsql-general@postgresql.org, pgsql-jdbc@postgresql.org
|
||||
Subject: Re: [JDBC] [GENERAL] java stored procedures
|
||||
References: <3C074DE4.9040905@freemail.hu> <3C0BE325.3020809@xythos.com> <3C0C937E.9000405@freemail.hu> <3C0CFD82.1030600@xythos.com> <3C0D219C.1090804@freemail.hu>
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Status: OR
|
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|
||||
Laszlo,
|
||||
|
||||
|
||||
> I am very far from features like this.
|
||||
> PL/JAVA now:
|
||||
> -there is a separate process running java (kaffe). this process creates
|
||||
> a sys v message queue, that holds requests. almost forgot, a shared
|
||||
> memory segment too. I didn`t find better way to tell postgres the
|
||||
> informations about the java process.
|
||||
|
||||
|
||||
Does the mechanism you are planning support running any JVM? In my
|
||||
opionion Kaffe isn't good enough to be widely useful. I think you
|
||||
should be able to plugin whatever jvm is best on your platform, which
|
||||
will likely be either the Sun or IBM JVMs.
|
||||
|
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Also, can you explain this a little bit more. How does the jvm process
|
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get started? (I would hope that the postgresql server processes would
|
||||
start it when needed, as opposed to requiring that it be started
|
||||
separately.) How does the jvm access these shared memory structures?
|
||||
Since there aren't any methods in the java API to do such things that I
|
||||
am aware of.
|
||||
|
||||
> -the java request_handler function on the server side attaches to the
|
||||
> shared memory, reads the key of the message queue., attaches to it,
|
||||
> sends the data of the function, and a signal for the pl/java. after, it
|
||||
> is waiting for a signal from the java thread.
|
||||
|
||||
|
||||
I don't understand how you do this in java? I must not be understanding
|
||||
something correctly here.
|
||||
|
||||
> -when java thread receives the signal, it reads the message(s) from the
|
||||
> queue, and starts some actions. When done it tells postgres with a
|
||||
> signal that it is ready, and it can come for its results. This will be
|
||||
> rewritten see below problems.
|
||||
|
||||
|
||||
Are signals the best way to accomplish this?
|
||||
|
||||
> -And postgres is runing, while java is waiting for postgres to say
|
||||
> something.
|
||||
|
||||
|
||||
But in reality if the postgres process is executing a stored function it
|
||||
needs to wait for the result of that function call before continuing
|
||||
doesn't it?
|
||||
|
||||
>
|
||||
> Threading on the java process side is not done yet, ok, it is not that
|
||||
> hard, I will write it, if it will be realy neccessary.
|
||||
|
||||
|
||||
Agreed, this is important.
|
||||
|
||||
>
|
||||
> The problems, for now:
|
||||
> I had a very simple system, that passed a very limited scale of argument
|
||||
> types, with a very limited quantity of parameters (int, varchar, bool).
|
||||
> Postgres has limits for the argument count too, but not for types. It
|
||||
> had too much limits, so I am working (or to tell the truth now only
|
||||
> thinking) on a new type handling that fits the felxibility of
|
||||
> Postgresql`s type flexibility. For this I will have to learn a lot about
|
||||
> Postgres`s type system. This will be my program this weekend. :)
|
||||
|
||||
|
||||
Shouldn't this code use all or most of the logic found in the FE/BE
|
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protocol? Why invent and code another mechanism to transfer data when
|
||||
one already exists. (I will admit that the current FE/BE mechanism
|
||||
isn't the ideal choice, but it seems easier to reuse what exists for now
|
||||
and improve on it later).
|
||||
|
||||
|
||||
>
|
||||
> thanks,
|
||||
> Laszlo Hornyak
|
||||
>
|
||||
|
||||
You didn't mention how you plan to deal with the transaction symantics.
|
||||
So what happens when the pl/java function calls through jdbc back to
|
||||
the server to insert some data? That should happen in the same
|
||||
transaction as the caller correct?
|
||||
|
||||
thanks,
|
||||
--Barry
|
||||
|
||||
|
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From pgsql-jdbc-owner+M2559@postgresql.org Thu Dec 6 10:18:55 2001
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Date: Wed, 05 Dec 2001 10:06:10 +0100
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From: Laszlo Hornyak <hornyakl@freemail.hu>
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To: Barry Lind <barry@xythos.com>
|
||||
cc: hornyakl@users.sourceforge.net, pgsql-general@postgresql.org,
|
||||
pgsql-jdbc@postgresql.org
|
||||
Subject: Re: [JDBC] [GENERAL] java stored procedures
|
||||
References: <3C074DE4.9040905@freemail.hu> <3C0BE325.3020809@xythos.com> <3C0C937E.9000405@freemail.hu> <3C0CFD82.1030600@xythos.com> <3C0D219C.1090804@freemail.hu> <3C0D799D.4010808@xythos.com>
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Status: OR
|
||||
|
||||
Hi!
|
||||
|
||||
Barry Lind wrote:
|
||||
|
||||
> Does the mechanism you are planning support running any JVM? In my
|
||||
> opionion Kaffe isn't good enough to be widely useful. I think you
|
||||
> should be able to plugin whatever jvm is best on your platform, which
|
||||
> will likely be either the Sun or IBM JVMs.
|
||||
|
||||
Ok, I also had problems with caffe, but it may work. I like it becouse
|
||||
it is small (the source is about 6M). As much as I know Java VM`s has a
|
||||
somewhat standard native interface called JNI. I use this to start the
|
||||
VM, and communicate with it. If you think I should change I will do it,
|
||||
but it may take a long time to get the new VM. For then I have to run kaffe.
|
||||
|
||||
> Also, can you explain this a little bit more. How does the jvm
|
||||
> process get started? (I would hope that the postgresql server
|
||||
> processes would start it when needed, as opposed to requiring that it
|
||||
> be started separately.) How does the jvm access these shared memory
|
||||
> structures? Since there aren't any methods in the java API to do such
|
||||
> things that I am aware of.
|
||||
|
||||
JVM does not. 'the java process' does with simple posix calls. I use
|
||||
debian potatoe, on any other posix system it should work, on any other
|
||||
somewhat posix compatible system it may work, I am not sure...
|
||||
|
||||
>
|
||||
> I don't understand how you do this in java? I must not be
|
||||
> understanding something correctly here.
|
||||
|
||||
My failure.
|
||||
The 'java request_handler' is not a java function, it is the C
|
||||
call_handler in the Postgres side, that is started when a function of
|
||||
language 'pljava' is called.
|
||||
I made some failure in my previous mail. At home I named the pl/java
|
||||
language pl/pizza (something that is not caffe, but well known enough
|
||||
:). The application has two running binaries:
|
||||
-pizza (which was called 'java process' last time) This is a small C
|
||||
program that uses JNI to start VM and call java methods.
|
||||
-plpizza.so the shared object that contains the call_handler function.
|
||||
|
||||
|
||||
>
|
||||
>
|
||||
>> -when java thread receives the signal, it reads the message(s) from
|
||||
>> the queue, and starts some actions. When done it tells postgres with
|
||||
>> a signal that it is ready, and it can come for its results. This will
|
||||
>> be rewritten see below problems.
|
||||
>
|
||||
>
|
||||
>
|
||||
> Are signals the best way to accomplish this?
|
||||
|
||||
I don`t know if it is the best, it is the only way I know :)
|
||||
Do you know any other ways?
|
||||
|
||||
>
|
||||
>
|
||||
>> -And postgres is runing, while java is waiting for postgres to say
|
||||
>> something.
|
||||
>
|
||||
> But in reality if the postgres process is executing a stored function
|
||||
> it needs to wait for the result of that function call before
|
||||
> continuing doesn't it?
|
||||
|
||||
Surely, this is done. How could Postgres tell the result anyway ? :)
|
||||
|
||||
>
|
||||
>>
|
||||
>> Threading on the java process side is not done yet, ok, it is not
|
||||
>> that hard, I will write it, if it will be realy neccessary.
|
||||
>
|
||||
> Agreed, this is important.
|
||||
>
|
||||
> Shouldn't this code use all or most of the logic found in the FE/BE
|
||||
> protocol? Why invent and code another mechanism to transfer data when
|
||||
> one already exists. (I will admit that the current FE/BE mechanism
|
||||
> isn't the ideal choice, but it seems easier to reuse what exists for
|
||||
> now and improve on it later).
|
||||
|
||||
Well, I am relatively new to Postgres, and I don`t know these protocols.
|
||||
In the weekend I will start to learn it, and in Sunday or Monday I maybe
|
||||
I will understand it, if not, next weekend..
|
||||
|
||||
>
|
||||
> You didn't mention how you plan to deal with the transaction
|
||||
> symantics. So what happens when the pl/java function calls through
|
||||
> jdbc back to the server to insert some data? That should happen in
|
||||
> the same transaction as the caller correct?
|
||||
|
||||
I don`t think this will be a problem, I have ideas for this. Idea mean:
|
||||
I know how I will start it, it may be good, or it may be fataly stupid
|
||||
idea, it will turn out when I tried it. Simply: The same way plpizza
|
||||
tells pizza the request, pizza can talk back to plpizza. This is planed
|
||||
to work with similar mechanism I described last time (shm+signals).
|
||||
|
||||
Monday I will try to send a little pieces of code to make thing clear, ok?
|
||||
|
||||
thanks,
|
||||
Laszlo Hornyak
|
||||
|
||||
|
||||
---------------------------(end of broadcast)---------------------------
|
||||
TIP 1: subscribe and unsubscribe commands go to majordomo@postgresql.org
|
||||
|
||||
From pgsql-jdbc-owner+M2567@postgresql.org Thu Dec 6 12:05:50 2001
|
||||
Return-path: <pgsql-jdbc-owner+M2567@postgresql.org>
|
||||
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|
||||
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|
||||
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|
||||
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|
||||
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|
||||
Received: from barry.xythos.com (h-64-105-36-191.SNVACAID.covad.net [64.105.36.191])
|
||||
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|
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|
||||
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|
||||
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|
||||
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|
||||
Wed, 5 Dec 2001 09:32:19 -0800
|
||||
Message-ID: <3C0E5A23.7060701@xythos.com>
|
||||
Date: Wed, 05 Dec 2001 09:32:19 -0800
|
||||
From: Barry Lind <barry@xythos.com>
|
||||
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.6) Gecko/20011120
|
||||
X-Accept-Language: en-us
|
||||
MIME-Version: 1.0
|
||||
To: hornyakl@users.sourceforge.net
|
||||
cc: pgsql-hackers@postgresql.org, pgsql-jdbc@postgresql.org
|
||||
Subject: Re: [JDBC] [GENERAL] java stored procedures
|
||||
References: <3C074DE4.9040905@freemail.hu> <3C0BE325.3020809@xythos.com> <3C0C937E.9000405@freemail.hu> <3C0CFD82.1030600@xythos.com> <3C0D219C.1090804@freemail.hu> <3C0D799D.4010808@xythos.com> <3C0DE382.1050400@freemail.hu>
|
||||
Content-Type: text/plain; charset=us-ascii; format=flowed
|
||||
Content-Transfer-Encoding: 7bit
|
||||
Precedence: bulk
|
||||
Sender: pgsql-jdbc-owner@postgresql.org
|
||||
Status: OR
|
||||
|
||||
Laszlo,
|
||||
|
||||
I have cc'ed the hackers mail list since that group of developers is
|
||||
probably better able than I to make suggestions on the best interprocess
|
||||
communication mechanism to use for this. See
|
||||
http://archives2.us.postgresql.org/pgsql-general/2001-12/msg00092.php
|
||||
for background on this thread.
|
||||
|
||||
I also stopped cc'ing the general list, since this is getting too
|
||||
detailed for most of the members on that list.
|
||||
|
||||
Now to your mail:
|
||||
|
||||
Laszlo Hornyak wrote:
|
||||
|
||||
> Hi!
|
||||
>
|
||||
> Barry Lind wrote:
|
||||
>
|
||||
>> Does the mechanism you are planning support running any JVM? In my
|
||||
>> opionion Kaffe isn't good enough to be widely useful. I think you
|
||||
>> should be able to plugin whatever jvm is best on your platform, which
|
||||
>> will likely be either the Sun or IBM JVMs.
|
||||
>
|
||||
>
|
||||
> Ok, I also had problems with caffe, but it may work. I like it becouse
|
||||
> it is small (the source is about 6M). As much as I know Java VM`s has a
|
||||
> somewhat standard native interface called JNI. I use this to start the
|
||||
> VM, and communicate with it. If you think I should change I will do it,
|
||||
> but it may take a long time to get the new VM. For then I have to run
|
||||
> kaffe.
|
||||
>
|
||||
|
||||
|
||||
This seems like a reasonable approach and should work across different
|
||||
JVMs. It would probably be a good experiment to try this with the Sun
|
||||
or IBM jvm at some point to verify. What I was afraid of was that you
|
||||
were hacking the Kaffe code to perform the integration which would limit
|
||||
this solution to only using Kaffe.
|
||||
|
||||
|
||||
>> Also, can you explain this a little bit more. How does the jvm
|
||||
>> process get started? (I would hope that the postgresql server
|
||||
>> processes would start it when needed, as opposed to requiring that it
|
||||
>> be started separately.) How does the jvm access these shared memory
|
||||
>> structures? Since there aren't any methods in the java API to do such
|
||||
>> things that I am aware of.
|
||||
>
|
||||
>
|
||||
> JVM does not. 'the java process' does with simple posix calls. I use
|
||||
> debian potatoe, on any other posix system it should work, on any other
|
||||
> somewhat posix compatible system it may work, I am not sure...
|
||||
>
|
||||
>>
|
||||
>> I don't understand how you do this in java? I must not be
|
||||
>> understanding something correctly here.
|
||||
>
|
||||
>
|
||||
> My failure.
|
||||
> The 'java request_handler' is not a java function, it is the C
|
||||
> call_handler in the Postgres side, that is started when a function of
|
||||
> language 'pljava' is called.
|
||||
> I made some failure in my previous mail. At home I named the pl/java
|
||||
> language pl/pizza (something that is not caffe, but well known enough
|
||||
> :). The application has two running binaries:
|
||||
> -pizza (which was called 'java process' last time) This is a small C
|
||||
> program that uses JNI to start VM and call java methods.
|
||||
> -plpizza.so the shared object that contains the call_handler function.
|
||||
>
|
||||
|
||||
|
||||
Just a suggestion: PL/J might be a good name, since as you probably
|
||||
know it can't be called pl/java because of the trademark restrictions on
|
||||
the word 'java'.
|
||||
|
||||
I am a little concerned about the stability and complexity of having
|
||||
this '-pizza' program be responsible for handling the calls on the java
|
||||
side. My concern is that this will need to be a multithreaded program
|
||||
since multiple backends will concurrently be needing to interact with
|
||||
multiple java threads through this one program. It might be simpler if
|
||||
each postgres process directly communicated to a java thread via a tcpip
|
||||
socket. Then the "-pizza" program would only need to be responsible for
|
||||
starting up the jvm and creating java threads and sockets for a postgres
|
||||
process (it would perform a similar role to postmaster for postgres
|
||||
client connections).
|
||||
|
||||
|
||||
>
|
||||
>>
|
||||
>>
|
||||
>>> -when java thread receives the signal, it reads the message(s) from
|
||||
>>> the queue, and starts some actions. When done it tells postgres with
|
||||
>>> a signal that it is ready, and it can come for its results. This will
|
||||
>>> be rewritten see below problems.
|
||||
>>
|
||||
>>
|
||||
>>
|
||||
>>
|
||||
>> Are signals the best way to accomplish this?
|
||||
>
|
||||
>
|
||||
> I don`t know if it is the best, it is the only way I know :)
|
||||
> Do you know any other ways?
|
||||
>
|
||||
|
||||
|
||||
I don't know, but hopefully someone on the hackers list will chip in
|
||||
here with a comment.
|
||||
|
||||
|
||||
>>
|
||||
>>>
|
||||
>>> Threading on the java process side is not done yet, ok, it is not
|
||||
>>> that hard, I will write it, if it will be realy neccessary.
|
||||
>>
|
||||
>>
|
||||
>> Agreed, this is important.
|
||||
>>
|
||||
>> Shouldn't this code use all or most of the logic found in the FE/BE
|
||||
>> protocol? Why invent and code another mechanism to transfer data when
|
||||
>> one already exists. (I will admit that the current FE/BE mechanism
|
||||
>> isn't the ideal choice, but it seems easier to reuse what exists for
|
||||
>> now and improve on it later).
|
||||
>
|
||||
>
|
||||
> Well, I am relatively new to Postgres, and I don`t know these protocols.
|
||||
> In the weekend I will start to learn it, and in Sunday or Monday I maybe
|
||||
> I will understand it, if not, next weekend..
|
||||
>
|
||||
>>
|
||||
>> You didn't mention how you plan to deal with the transaction
|
||||
>> symantics. So what happens when the pl/java function calls through
|
||||
>> jdbc back to the server to insert some data? That should happen in
|
||||
>> the same transaction as the caller correct?
|
||||
>
|
||||
>
|
||||
> I don`t think this will be a problem, I have ideas for this. Idea mean:
|
||||
> I know how I will start it, it may be good, or it may be fataly stupid
|
||||
> idea, it will turn out when I tried it. Simply: The same way plpizza
|
||||
> tells pizza the request, pizza can talk back to plpizza. This is planed
|
||||
> to work with similar mechanism I described last time (shm+signals).
|
||||
>
|
||||
|
||||
|
||||
OK, so the same backend process that called the function gets messaged
|
||||
to process the sql. This should work. However it means you will need a
|
||||
special version of the jdbc driver that uses this shm+signals
|
||||
communication mechanism instead of what the current jdbc driver does.
|
||||
This is something I would be happy to help you with.
|
||||
|
||||
|
||||
|
||||
---------------------------(end of broadcast)---------------------------
|
||||
TIP 5: Have you checked our extensive FAQ?
|
||||
|
||||
http://www.postgresql.org/users-lounge/docs/faq.html
|
||||
|
||||
|
||||
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