config/5445: Can't Spawn Child Processes

[Dan Lee <dl...@dataimg.com>]

>Number:         5445
>Category:       config
>Synopsis:       Can't Spawn Child Processes
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          support
>Submitter-Id:   apache
>Arrival-Date:   Thu Dec  9 01:10:00 PST 1999
>Last-Modified:
>Originator:     dlp@dataimg.com
>Organization:
apache
>Release:        1.3.9
>Environment:
BSDI BSD/OS 4.0.1 Kernel #0 
Pentium 400 AMD, 256MB memory.

uname -a output: 
BSD/OS dit4.cdmachine.com 4.0.1 BSDI BSD/OS 4.0.1 Kernel #0: Tue Nov 16 14:27:10
 PST 1999     tonyw@dit4.cdmachine.com:/usr/src/sys/compile/dit4  i386 
>Description:
This is an intermittent error that occurs when a cgi script "nph-new" attempts to run. The exact error from the error_log:

Internal Server Error
Resource temporarily unavailable: couldn't spawn child process: /var/www/cgi-bin/nph-new 

Here is our http.conf file:

##
## httpd.conf -- Apache HTTP server configuration file
##

# This is the main server configuration file. See URL http://www.apache.org/
# for instructions.

# Do NOT simply read the instructions in here without understanding
# what they do, if you are unsure consult the online docs. You have been
# warned.  

# Originally by Rob McCool

# Dynamic Shared Object (DSO) Support
#
# To be able to use the functionality of a module which was built as a DSO you
# have to place corresponding `LoadModule' lines at this location so the
# directives contained in it are actually available _before_ they are used.
# Please read the file README.DSO in the Apache 1.3 distribution for more
# details about the DSO mechanism and run `httpd -l' for the list of already
# built-in (statically linked and thus always available) modules in your httpd
# binary.
#
# Example:
# LoadModule foo_module libexec/mod_foo.so

# ServerType is either inetd, or standalone.

ServerType standalone

# If you are running from inetd, go to "ServerAdmin".

# Port: The port the standalone listens to. For ports < 1023, you will
# need httpd to be run as root initially.

Port 80

# HostnameLookups: Log the names of clients or just their IP numbers
#   e.g.   www.apache.org (on) or 204.62.129.132 (off)
# The default is off because it'd be overall better for the net if people
# had to knowingly turn this feature on.

HostnameLookups on

# If you wish httpd to run as a different user or group, you must run
# httpd as root initially and it will switch.  

# User/Group: The name (or #number) of the user/group to run httpd as.
#  On SCO (ODT 3) use User nouser and Group nogroup
#  On HPUX you may not be able to use shared memory as nobody, and the
#  suggested workaround is to create a user www and use that user.
#  NOTE that some kernels refuse to setgid(Group) or semctl(IPC_SET)
#  when the value of (unsigned)Group is above 60000; 
#  don't use Group nogroup on these systems!

User www
Group www

# ServerAdmin: Your address, where problems with the server should be
# e-mailed.

ServerAdmin webmaster@cdmachine.com

# ServerRoot: The directory the server's config, error, and log files
# are kept in.
# NOTE!  If you intend to place this on a NFS (or otherwise network)
# mounted filesystem then please read the LockFile documentation,
# you will save yourself a lot of trouble.

ServerRoot "/var/www"

# BindAddress: You can support virtual hosts with this option. This option
# is used to tell the server which IP address to listen to. It can either
# contain "*", an IP address, or a fully qualified Internet domain name.
# See also the VirtualHost directive.

BindAddress *

# ErrorLog: The location of the error log file. If this does not start
# with /, ServerRoot is prepended to it.

ErrorLog /var/log/httpd/error_log

# LogLevel: Control the number of messages logged to the error_log.
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.

LogLevel warn

# The following directives define some format nicknames for use with
# a CustomLog directive (see below).

LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined
LogFormat "%h %l %u %t \"%r\" %>s %b" common
LogFormat "%{Referer}i -> %U" referer
LogFormat "%{User-agent}i" agent

# The location of the access logfile (Common Logfile Format).
# If this does not start with /, ServerRoot is prepended to it.

#CustomLog /var/log/httpd/access_log common

# If you would like to have an agent and referer logfile uncomment the
# following directives.

#CustomLog /var/log/httpd/referer_log referer
#CustomLog /var/log/httpd/agent_log agent

# If you prefer a single logfile with access, agent and referer information
# (Combined Logfile Format) you can use the following directive.

CustomLog /var/log/httpd/access_log combined

# PidFile: The file the server should log its pid to
PidFile /var/run/httpd.pid

# ScoreBoardFile: File used to store internal server process information.
# Not all architectures require this.  But if yours does (you'll know because
# this file is created when you run Apache) then you *must* ensure that
# no two invocations of Apache share the same scoreboard file.
ScoreBoardFile /var/run/httpd.scoreboard

# The LockFile directive sets the path to the lockfile used when Apache
# is compiled with either USE_FCNTL_SERIALIZED_ACCEPT or
# USE_FLOCK_SERIALIZED_ACCEPT. This directive should normally be left at
# its default value. The main reason for changing it is if the logs
# directory is NFS mounted, since the lockfile MUST BE STORED ON A LOCAL
# DISK. The PID of the main server process is automatically appended to
# the filename. 
#
#LockFile /var/run/httpd.lock

# ExtendedStatus controls whether Apache will generate "full" status
# information (ExtendedStatus On) or just basic information (ExtendedStatus
# Off) when the server-status Handler is called. The default is Off.
#
ExtendedStatus On

# ServerName allows you to set a host name which is sent back to clients for
# your server if it's different than the one the program would get (i.e. use
# "www" instead of the host's real name).
#
# Note: You cannot just invent host names and hope they work. The name you 
# define here must be a valid DNS name for your host. If you don't understand
# this, ask your network administrator.
# If your host doesn't have a registered DNS name, enter its IP address here.
# You will have to access it by its address (e.g., http://123.45.67.89)
# anyway, and this will make redirections work in a sensible way.

ServerName www.cdmachine.com

# Optionally add a line containing the server version and virtual host
# name to server-generated pages (error documents, ftp directory listings,
# mod_status and mod_info output etc., but not SSI generated documents).
# Set to "EMail" to also include a mailto: link to the ServerAdmin.
# Set to one of:  On | Off | EMail
ServerSignature on

# UseCanonicalName:  (new for 1.3)  With this setting turned on, whenever
# Apache needs to construct a self-referencing URL (a url that refers back
# to the server the response is coming from) it will use ServerName and
# Port to form a "canonical" name.  With this setting off, Apache will
# use the hostname:port that the client supplied, when possible.  This
# also affects SERVER_NAME and SERVER_PORT in CGIs.
UseCanonicalName on

# CacheNegotiatedDocs: By default, Apache sends Pragma: no-cache with each
# document that was negotiated on the basis of content. This asks proxy
# servers not to cache the document. Uncommenting the following line disables
# this behavior, and proxies will be allowed to cache the documents.

#CacheNegotiatedDocs

# Timeout: The number of seconds before receives and sends time out

Timeout 1200

# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.

KeepAlive On

# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.

MaxKeepAliveRequests 100

# KeepAliveTimeout: Number of seconds to wait for the next request

KeepAliveTimeout 15

# Server-pool size regulation.  Rather than making you guess how many
# server processes you need, Apache dynamically adapts to the load it
# sees --- that is, it tries to maintain enough server processes to
# handle the current load, plus a few spare servers to handle transient
# load spikes (e.g., multiple simultaneous requests from a single
# Netscape browser).

# It does this by periodically checking how many servers are waiting
# for a request.  If there are fewer than MinSpareServers, it creates
# a new spare.  If there are more than MaxSpareServers, some of the
# spares die off.  These values are probably OK for most sites ---

MinSpareServers 10
MaxSpareServers 20

# Number of servers to start --- should be a reasonable ballpark figure.

StartServers 10

# Limit on total number of servers running, i.e., limit on the number
# of clients who can simultaneously connect --- if this limit is ever
# reached, clients will be LOCKED OUT, so it should NOT BE SET TOO LOW.
# It is intended mainly as a brake to keep a runaway server from taking
# Unix with it as it spirals down...

MaxClients 150

# MaxRequestsPerChild: the number of requests each child process is
#  allowed to process before the child dies.
#  The child will exit so as to avoid problems after prolonged use when
#  Apache (and maybe the libraries it uses) leak.  On most systems, this
#  isn't really needed, but a few (such as Solaris) do have notable leaks
#  in the libraries.

MaxRequestsPerChild 30

# Proxy Server directives. Uncomment the following line to
# enable the proxy server:

#ProxyRequests On

# Enable/disable the handling of HTTP/1.1 "Via:" headers.
# ("Full" adds the server version; "Block" removes all outgoing Via: headers)
# Set to one of: Off | On | Full | Block
#ProxyVia on

# To enable the cache as well, edit and uncomment the following lines:
# (no cacheing without CacheRoot)

#CacheRoot /var/www/proxy

#CacheSize 5
#CacheGcInterval 4
#CacheMaxExpire 24
#CacheLastModifiedFactor 0.1
#CacheDefaultExpire 1
#NoCache a_domain.com another_domain.edu joes.garage_sale.com

# Listen: Allows you to bind Apache to specific IP addresses and/or
# ports, in addition to the default. See also the VirtualHost command

#Listen 3000
#Listen 12.34.56.78:80

# VirtualHost: Allows the daemon to respond to requests for more than one
# server address, if your server machine is configured to accept IP packets
# for multiple addresses. This can be accomplished with the ifconfig 
# alias flag, or through kernel patches like VIF.

# Any httpd.conf or srm.conf directive may go into a VirtualHost command.
# See also the BindAddress entry.
 
#<VirtualHost host.some_domain.com>
#ServerAdmin webmaster@host.some_domain.com
#DocumentRoot /www/docs/host.some_domain.com
#ServerName host.some_domain.com
#ErrorLog logs/host.some_domain.com-error_log
#TransferLog logs/host.some_domain.com-access_log
#</VirtualHost>



>How-To-Repeat:
http://www.cdmachine.com
selecting enter starts the cgi script which runs our shopping cart cgi
Problem is very intermittent 
>Fix:
I sent our http.conf file. Please advise if our configuration could be causing this problem. When we had MinSpareServers and MaxSpareServers set to a higher amount the server would get this error every time. We reduced the amounts to 10 and 20 respectively and the problem now occurs only intermittently. If we ever need to raise the minspareservers and maxspareservers amount, the server will not run the cgi at all. 

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