Fatal Error : Invalid Memory alloc request size 1236252631

On 14 August 2023 11:59:26 CEST, Sai Teja <saitejasaichintalapudi@gmail.com> wrote:

Hi Team,

We are trying to fetch the one row of data (bytea data) for one table in
But getting the error stating that "Invalid Memory alloc request size
1236252631"

The row which we were trying to fetch have one bytea column which is more
than 1GB

Could anyone please help me to resolve this issue.

You can try to change the bytea_output. Possible values are hex and escape. With some luck it will work, but maybe your application will have problems with that.

Andreas

Could anyone please suggest any ideas to resolve this issue.

I have increased the below parameters but still I'm getting same error.

work_mem, shared_buffers

Out of 70k rows in the table only for the few rows which is of large size
(700MB) getting the issue. Am unable to fetch the data for that particular
row.

Would be appreciated if anyone share the insights.

Thanks,
Sai

On Mon, 14 Aug, 2023, 5:21 pm Sai Teja, <saitejasaichintalapudi@gmail.com>
wrote:

On 8/14/23 09:29, Sai Teja wrote:

Could anyone please suggest any ideas to resolve this issue.

I have increased the below parameters but still I'm getting same error.

work_mem, shared_buffers

Out of 70k rows in the table only for the few rows which is of large
size (700MB) getting the issue. Am unable to fetch the data for that
particular row.

Would be appreciated if anyone share the insights.

Thanks,
Sai

Are you using java?  There's an upper limit on array size, hence also on
String length.  You'll likely need to process the output in chunks.

I am just running select query to fetch the result
Query : select id, content_data, name from table_name
So here content_data is bytea content which is having more than 700 MB.
Even if I run this query in any DB client such as Pgadmin, dbeaver etc..
I'm facing the same error. But this query is being called in java as well
So, I don't think java could be the issue as I can able to successfully
insert the data. But, only the problem is with fetching the data that too
only specific rows which are having huge volume of data.

Thanks,
Sai

On Mon, 14 Aug, 2023, 10:55 pm Rob Sargent, <robjsargent@gmail.com> wrote:

Did you /try/ changing bytea_output to hex?

On 8/14/23 12:31, Sai Teja wrote:

I am just running select query to fetch the result
Query : select id, content_data, name from table_name
So here content_data is bytea content which is having more than 700 MB.
Even if I run this query in any DB client such as Pgadmin, dbeaver etc..
I'm facing the same error. But this query is being called in java as well
So, I don't think java could be the issue as I can able to successfully
insert the data. But, only the problem is with fetching the data that too
only specific rows which are having huge volume of data.

Thanks,
Sai

On Mon, 14 Aug, 2023, 10:55 pm Rob Sargent, <robjsargent@gmail.com> wrote:

On 8/14/23 09:29, Sai Teja wrote:

Could anyone please suggest any ideas to resolve this issue.

I have increased the below parameters but still I'm getting same error.

work_mem, shared_buffers

Out of 70k rows in the table only for the few rows which is of large
size (700MB) getting the issue. Am unable to fetch the data for that
particular row.

Would be appreciated if anyone share the insights.

Thanks,
Sai

Are you using java?  There's an upper limit on array size, hence also on
String length.  You'll likely need to process the output in chunks.

--
Born in Arizona, moved to Babylonia.

By default the bytea_output is in hex format.

On Tue, 15 Aug, 2023, 12:44 am Ron, <ronljohnsonjr@gmail.com> wrote:

Hi team,

I got to know the field size limit for the bytea datatype column is limited
to 1 GB in postgreSQL. Then how can we increase this? Since we need to
store high volume of data for each row in a table

https://www.postgresql.org/docs/current/limits.html

Any suggestions would be appreciated.

Thanks & Regards,
Sai

On Tue, 15 Aug, 2023, 8:10 am Sai Teja, <saitejasaichintalapudi@gmail.com>
wrote:

Sai Teja <saitejasaichintalapudi@gmail.com> writes:

I got to know the field size limit for the bytea datatype column is limited
to 1 GB in postgreSQL. Then how can we increase this?

You can't. That limit is wired-in in many ways. Think about how to
split your data across multiple table rows.

regards, tom lane

Hi Team,

Even I used postgreSQL Large Objects by referring this link to store and
retrieve large files (As bytea not working)
https://www.postgresql.org/docs/current/largeobjects.html

But even now I am unable to fetch the data at once from large objects

select lo_get(oid);

Here I'm getting the same error message.

But if I use select data from pg_large_object where loid = 49374
Then I can fetch the data but in page wise (data splitting into rows of
each size 2KB)

So, here how can I fetch the data at single step rather than page by page
without any error.

And I'm just wondering how do many applications storing huge amount of data
in GBs? I know that there is 1GB limit for each field set by postgreSQL. If
so, how to deal with these kind of situations? Would like to know about
this to deal with real time scenarios.

We need to store large content (huge volume of data) and retrieve it.
Currently It is not happening due to limit of field size set by postgreSQL.

Would request to share your insights and suggestions on this to help me for
resolving this issue.

Thanks & Regards,
Sai Teja

On Tue, 15 Aug, 2023, 8:53 am Tom Lane, <tgl@sss.pgh.pa.us> wrote:

 
Even I used postgreSQL Large Objects by referring this link to store and retrieve large files (As bytea not working)
https://www.postgresql.org/docs/current/largeobjects.html
 
But even now I am unable to fetch the data at once from large objects
 
select lo_get(oid);
 
Here I'm getting the same error message.
 
But if I use select data from pg_large_object where loid = 49374
Then I can fetch the data but in page wise (data splitting into rows of each size 2KB)
 
So, here how can I fetch the data at single step rather than page by page without any error.
 
And I'm just wondering how do many applications storing huge amount of data in GBs? I know that there is 1GB limit for each field set by postgreSQL. If so, how to deal with these kind of situations? Would like to know about this to deal with real time scenarios.

https://github.com/lzlabs/pg_dumpbinary/blob/master/README.md
might be of help

Karsten

Hi

čt 17. 8. 2023 v 16:48 odesílatel Karsten Hilbert <Karsten.Hilbert@gmx.net>
napsal:

Even I used postgreSQL Large Objects by referring this link to store and
retrieve large files (As bytea not working)
https://www.postgresql.org/docs/current/largeobjects.html

But even now I am unable to fetch the data at once from large objects

select lo_get(oid);

Here I'm getting the same error message.

But if I use select data from pg_large_object where loid = 49374
Then I can fetch the data but in page wise (data splitting into rows of
each size 2KB)

So, here how can I fetch the data at single step rather than page by page
without any error.

SQL functionality is limited by 1GB

You should to use \lo_import or \lo_export commands

or special API https://www.postgresql.org/docs/current/lo-interfaces.html

regards

Pavel

On 8/17/23 07:35, Sai Teja wrote:

Hi Team,

Even I used postgreSQL Large Objects by referring this link to store
and retrieve large files (As bytea not working)
https://www.postgresql.org/docs/current/largeobjects.html

But even now I am unable to fetch the data at once from large objects

select lo_get(oid);

Here I'm getting the same error message.

But if I use select data from pg_large_object where loid = 49374
Then I can fetch the data but in page wise (data splitting into rows
of each size 2KB)

So, here how can I fetch the data at single step rather than page by
page without any error.

And I'm just wondering how do many applications storing huge amount of
data in GBs? I know that there is 1GB limit for each field set by
postgreSQL. If so, how to deal with these kind of situations? Would
like to know about this to deal with real time scenarios.

We need to store large content (huge volume of data) and retrieve it.
Currently It is not happening due to limit of field size set by
postgreSQL.

Would request to share your insights and suggestions on this to help
me for resolving this issue.

My first attempt at handling large payload was to use Java Selector
directly in my app.  This worked but manually chunking the data was
tricky.  I switched to using Tomcat and it handles large http(s)
payloads seamlessly.