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ORA-04030 When Clients Connect Across Network Using SQL*Net (Doc ID 753439.1)

Last updated on MARCH 05, 2020

Applies to:

Oracle Database - Enterprise Edition - Version and later
Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.


You may see the one or more of the following scenarios:

- Alert log shows error ORA-04030 when connecting remotely using SQL*Net:

ORA-04030: out of process memory when trying to allocate 258072 bytes (QERGH hash-agg,kllcqas:kllsltba)

- Local connection works without any errors and user process is using about 142 MB of PGA for the session.

- Increased the parameter pga_aggregate_target to 5G or more but the error still occurs:

ALTER SYSTEM SET pga_aggregate_target='5000M' SCOPE=SPFILE SID='*';

- A heapdump shows a user process is using about 100M of PGA for the session when connecting via SQL*NET which is less than the memory used during local connection.

 event= '4030 trace name heapdump level 536870917;name errorstack level 3'


The following unix/linux OS limits are set to unlimited:

ulimit -aH

time(seconds) unlimited
file(blocks) unlimited
data(kbytes) unlimited
stack(kbytes) unlimited
memory(kbytes) unlimited
coredump(blocks) unlimited
nofiles(descriptors) unlimited

The following unix/linux OS parameters are also set in the file /etc/security/limits for Oracle user and OS user but problem still occurs:

fsize = -1
core = -1
cpu = -1
data = =-1
stack = -1
rss = -1
nofiles = -1

but problems still persist.


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