ORA-27302: Failure Occurred At Skgpspawn - Process Spawn Errors

ORA-27302: Failure Occurred at: skgpspawn3

Error Overview

Error Text: ORA-27302: failure occurred at: skgpspawnN

ORA-27302 reports the location within Oracle’s process spawn code where a failure occurred. It almost always appears in tandem with ORA-27300 (OS system dependent operation failed) and ORA-27301 (OS failure message). The “skgpspawn” prefix refers to Oracle’s process creation kernel layer; the suffix number identifies the failure point.

Skgpspawn Location Codes

Suffix	Failure point	Common causes
skgpspawn1	fork()	Process limit, memory exhaustion
skgpspawn2	exec setup	Permission, library loading
skgpspawn3	parent post-fork	Communication with child failed
skgpspawn4	child setup	Child process initialization error
skgpspawn5	exec()	Binary missing or unreadable
skgpspawn6	wait/cleanup	Process state corruption
skgpspawn8	shadow process	Server process spawn failure
skgpspawn15	RAC interconnect	Network process spawn

Common Causes

Process Limit Reached

• ulimit nproc for Oracle user too low
• System-wide /proc/sys/kernel/pid_max exhausted
• Cgroup pid limit reached on container
• Too many existing Oracle processes

Memory Exhaustion

• Insufficient memory for fork()
• Overcommit denied (vm.overcommit_memory)
• Swap exhausted
• HugePages misconfigured

Permission and File Issues

• Oracle binary lost executable bit
• oracle binary on read-only mount
• SELinux denying exec
• Library path issues (LD_LIBRARY_PATH)

Resource Limits

• ulimit nofile too low (file descriptors)
• ulimit memlock too low for HugePages
• ulimit stack too low

Diagnostic Steps

Read Full Error Stack

ORA-27300: OS system dependent operation:fork failed with status: 11
ORA-27301: OS failure message: Resource temporarily unavailable
ORA-27302: failure occurred at: skgpspawn3

The OS message in ORA-27301 is the key indicator.

Check Process Counts

# Current Oracle process count
ps -ef | grep oracle | wc -l

# Running threads/processes for oracle user
ps --no-headers -u oracle | wc -l

# System-wide
ps -eLf | wc -l

# Per-user limits
sudo -u oracle bash -c 'ulimit -u'   # max user processes
sudo -u oracle bash -c 'ulimit -n'   # max open files

View Kernel Limits

# Maximum PIDs
cat /proc/sys/kernel/pid_max
cat /proc/sys/kernel/threads-max

# Memory overcommit
cat /proc/sys/vm/overcommit_memory
cat /proc/sys/vm/overcommit_ratio

# Free memory
free -h
cat /proc/meminfo | head -20

Inspect Limits Configuration

/etc/security/limits.conf

grep -E "^(oracle|grid)" /etc/security/limits.conf

# /etc/security/limits.d/
ls /etc/security/limits.d/
cat /etc/security/limits.d/99-oracle.conf

Check Alert Log Context

tail -200 $ORACLE_BASE/diag/rdbms/$ORACLE_SID/$ORACLE_SID/trace/alert_$ORACLE_SID.log \
    | grep -B5 -A15 "ORA-27302"

Resolution Steps

1. Increase ulimit Values

# /etc/security/limits.conf or /etc/security/limits.d/99-oracle.conf
oracle  soft  nproc    16384
oracle  hard  nproc    16384
oracle  soft  nofile   65536
oracle  hard  nofile   65536
oracle  soft  stack    10240
oracle  hard  stack    32768
oracle  soft  memlock  unlimited
oracle  hard  memlock  unlimited

grid    soft  nproc    16384
grid    hard  nproc    16384
grid    soft  nofile   65536
grid    hard  nofile   65536

After changes, oracle user must log in fresh:

# Verify in new session
ulimit -u
ulimit -n

2. Increase Kernel PID Max

# Temporary
echo 4194304 > /proc/sys/kernel/pid_max

# Permanent in /etc/sysctl.conf
kernel.pid_max = 4194304

# Apply
sysctl -p

3. Fix Memory Overcommit Settings

# Allow overcommit (default for Oracle)
echo 1 > /proc/sys/vm/overcommit_memory

# Permanent
# /etc/sysctl.conf
vm.overcommit_memory = 1
vm.overcommit_ratio = 95
sysctl -p

4. Free Resources

# Find and kill orphan/zombie processes
ps -ef | grep oracle | grep -v grep | wc -l

# Find sessions safe to kill
sqlplus / as sysdba <<EOF
SELECT s.sid, s.serial#, s.username, s.program, s.status,
       p.spid
FROM v\$session s, v\$process p
WHERE s.paddr = p.addr
AND s.status = 'INACTIVE'
AND s.last_call_et > 86400  -- 24 hours
ORDER BY s.last_call_et DESC;
EOF

# Kill specific session
sqlplus / as sysdba <<EOF
ALTER SYSTEM KILL SESSION 'sid,serial#' IMMEDIATE;
EOF

5. Validate Oracle Binary

# Check oracle binary
ls -la $ORACLE_HOME/bin/oracle
# Should be -rwsr-s--x  oracle  oinstall

# Fix if permissions wrong
chmod 6751 $ORACLE_HOME/bin/oracle
chown oracle:oinstall $ORACLE_HOME/bin/oracle

# Validate libraries
ldd $ORACLE_HOME/bin/oracle | grep "not found"

6. SELinux Adjustments

# Check SELinux status
getenforce

# View denials
ausearch -m AVC -ts recent | grep -i oracle

# Set permissive temporarily for testing
setenforce 0

# If issue resolves, configure proper SELinux policy
# Permanent fix in /etc/selinux/config:
# SELINUX=permissive  (not recommended long-term)

# Or grant specific contexts
chcon -t lib_t /u01/app/oracle/product/19c/dbhome_1/lib/*

7. Container/Cgroup Limits

# Check cgroup limits (containers/k8s)
cat /sys/fs/cgroup/pids/pids.max
cat /sys/fs/cgroup/memory/memory.limit_in_bytes

# In Kubernetes, increase limits in pod spec
# resources:
#   limits:
#     memory: "32Gi"
#   requests:
#     memory: "16Gi"

Common Scenarios

Scenario 1: “Resource temporarily unavailable”

ORA-27300: OS system dependent operation:fork failed with status: 11
ORA-27301: OS failure message: Resource temporarily unavailable
ORA-27302: failure occurred at: skgpspawn3

Fix: Increase nproc in limits.conf and pid_max in sysctl.

Scenario 2: “Cannot allocate memory”

ORA-27300: OS system dependent operation:fork failed with status: 12
ORA-27301: OS failure message: Cannot allocate memory

Fix: Set vm.overcommit_memory = 1, add swap, or reduce SGA.

Scenario 3: “Permission denied”

ORA-27300: OS system dependent operation:exec failed with status: 13
ORA-27302: failure occurred at: skgpspawn5

Fix: Check oracle binary permissions and SELinux context.

Sample Output

SQL> CONNECT scott/tiger
ERROR:
ORA-12500: TNS:listener failed to start a dedicated server process

[oracle@host]$ tail -20 alert_PROD.log
Process P000 died, see its trace file
ORA-27300: OS system dependent operation:fork failed with status: 11
ORA-27301: OS failure message: Resource temporarily unavailable
ORA-27302: failure occurred at: skgpspawn3

[oracle@host]$ ps -u oracle | wc -l
4096

[oracle@host]$ ulimit -u
4096

# nproc limit reached
# Edit /etc/security/limits.d/99-oracle.conf:
# oracle hard nproc 16384

# Re-login and verify:
[oracle@host]$ ulimit -u
16384

Prevention Strategies

Pre-Install Validation Script

#!/bin/bash
# Validate Oracle prerequisites
ulimit_nproc=$(sudo -u oracle bash -c 'ulimit -u')
ulimit_nofile=$(sudo -u oracle bash -c 'ulimit -n')

if [ "$ulimit_nproc" -lt 16384 ]; then
    echo "FAIL: nproc=$ulimit_nproc, need >= 16384"
fi

if [ "$ulimit_nofile" -lt 65536 ]; then
    echo "FAIL: nofile=$ulimit_nofile, need >= 65536"
fi

pid_max=$(cat /proc/sys/kernel/pid_max)
if [ "$pid_max" -lt 1048576 ]; then
    echo "WARN: pid_max=$pid_max, recommend >= 1048576"
fi

Monitoring

#!/bin/bash
# Alert on high process counts
THRESHOLD=80  # percent of limit

LIMIT=$(sudo -u oracle bash -c 'ulimit -u')
CURRENT=$(ps -u oracle --no-headers | wc -l)
PCT=$(( CURRENT * 100 / LIMIT ))

if [ $PCT -gt $THRESHOLD ]; then
    echo "Oracle process count: $CURRENT/$LIMIT ($PCT%)" \
        | mail -s "Oracle nproc warning" [email protected]
fi

Connection Pool Tuning

-- Limit total sessions to prevent runaway process count
ALTER SYSTEM SET sessions = 1000 SCOPE=SPFILE;
ALTER SYSTEM SET processes = 800 SCOPE=SPFILE;
-- Restart required

-- Resource manager throttle
BEGIN
  DBMS_RESOURCE_MANAGER.CREATE_PLAN_DIRECTIVE(
    plan => 'DEFAULT_PLAN',
    group_or_subplan => 'OTHER_GROUPS',
    active_sess_pool_p1 => 50);
END;
/

Oracle Preinstall RPM

# RHEL/OL: install oracle-database-preinstall RPM
yum install -y oracle-database-preinstall-19c

# Sets all limits and kernel parameters per Oracle requirements

Related Errors

• ORA-12500: TNS:listener failed to start dedicated server
• ORA-27300: OS system dependent operation failed
• ORA-27301: OS failure message
• ORA-27303: Additional information
• ORA-04030: Out of process memory

Troubleshooting Checklist

• Read full error stack including ORA-27300/27301
• Decode skgpspawn suffix (1=fork, 5=exec, etc.)
• Check ulimit nproc, nofile, memlock
• Validate kernel pid_max and threads-max
• Verify oracle binary permissions and SELinux
• Check available memory and overcommit settings
• Install oracle-database-preinstall RPM if RHEL/OL
• Monitor process count proactively