|
Setting |
Description |
AOLserver 4.0 |
AOLserver 4.5.x |
| Section |
Parameter |
Default |
Section |
Parameter |
Default |
|
Thread Stack Size (bytes) |
ns/threads OR ns/parameters |
stacksize |
128k |
ns/threads OR ns/parameters |
stacksize |
128k |
|
stacksize
can also be set in ns/parameters but ns/threads
setting will override. Ancient versions of AOLserver
only needed this to be explicitly set on certain
platforms and otherwise used the OS default, which
under Windows, for example, is 1MB, so the default
AOLserver setting in current versions is quite low
for deeply-nested Tcl code. Note that
stacksize must be a multiple of 8k for AOLserver to
run under MacOS X. With RFE 975809
patch, stacksize can be set to 0 to make the OS
manage the stack size. NaviServer's
default is let the OS manage it. |
|
Maximum Number of Keepalive Connections |
ns/parameters |
maxkeepalive |
100 |
ns/parameters |
maxkeepalive |
100 |
|
In prior
versions of AOLserver this may have been under
ns/servers/$server. In
AOLserver 4.0 and newer, this setting exists but
appears to be non-operational |
|
Keepalive Enable/Disable |
ns/parameters |
keepalivetimeout |
30 |
ns/parameters |
keepalivetimeout |
30 |
|
In prior
versions of AOLserver this may have been under
ns/servers/$server.
Set to 0 to disable Keep-alive
support, any other value will enable Keep-alive but
won't actually configure the timeout, which is now
configured under the driver (see below). |
|
Minimum Number of Connection Servicing Threads |
ns/servers/$server AND
ns/servers/$server/pool/$pool |
minthreads |
0 |
ns/servers/$server via
ns_pools and pools.tcl but really process-wide |
minthreads |
0 |
|
In prior
versions of AOLserver, this was strictly per virtual
server. In AOLserver 4.0 and later,
there is the concept of separate connection thread
pools for certain mapped URLs, so this can be
configured either at the server level for the
default pool or for a specific pool.
Once AOLserver reaches this number of connection
threads, threads will be destroyed after an idle
timeout (see below). But once reached,
the number of threads will never drop below this
limit even after the idle timeout. |
|
Maximum Number of Connection Servicing Threads |
ns/servers/$server AND
ns/servers/$server/pool/$pool |
maxthreads |
10 |
ns/servers/$server via
ns_pools and pools.tcl but really process-wide |
maxthreads |
10 |
|
In prior
versions of AOLserver, this was strictly per virtual
server. In AOLserver 4.0 and later,
there is the concept of separate connection thread
pools for certain mapped URLs, so this can be
configured either at the server level for the
default pool or for a specific pool.
In AOLserver 4.0 if you set this above 100, you have
to set MaxConnections to the same number (see
below). In AOLserver 4.5, if the sum of maxthreads
for all the pools used in a particular virtual
server exceeds 100, and you actually want this
virtual server to have more than 100 connections,
you have to set the MaxSock setting to this sum plus
MaxWait plus MaxBusyThreads under the driver (see
below; our default nsd.tcl sets maxsock to 250 or
twice the server-level maxthreads value if it's over
125). Note that the default pool in
AOLserver 4.5 is now process-wide (shared by all
virtual servers) and the maxthreads setting in the
last virtual server processed at startup by
pools.tcl will override any other setting.
In addition, in AOLserver 4.5 there is a
default ns_limits -maxrun option defaulting to 100,
which you will have to increase as well to support
more concurrent threads than 100
(AM-modified pools.tcl will set the default -maxrun
limit to maxthreads).
Finally, you need to have enough concurrent
connections in your database pools configuration. |
|
Maximum Number of Connections Waiting to be Serviced |
|
|
|
ns/servers/$server via
ns_pools and AM-modified pools.tcl but really
process-wide |
MaxWait |
100 |
|
This
setting existed in AOLserver 2.x and was removed in
3.x - 4.0 as those versions did not support waiting
connections. The functionality is back
in AOLserver 4.5 via limits.
This setting is implemented by
AM-modified pools.tcl by calling ns_limits set
default -maxwait.
Any additional connections as well as any
connections that have been waiting for more than
MaxWaitTime are served with a 503 Error from the
Busy Error thread pool. |
|
Maximum Time for Connection to Wait to be Serviced |
|
|
|
ns/servers/$server via
ns_pools and AM-modified pools.tcl but really
process-wide |
MaxWaitTime |
60 |
|
This
setting is new to AOLserver 4.5 via limits and is
implemented by AM-modified pools.tcl by calling
ns_limits set default -timeout.
Connections that have been waiting for more than
MaxWaitTime seconds are served with a 503 Error from
the Busy Error thread pool. The
default of 60 seconds is a bit high - most clients
will not wait this long.
Note that the documentation for
ns_limits -timeout option was incorrect - it's not
the maximum time to 'run' (i.e. service) the
connection, it's the maximum time to wait to be run
before being overflown to the error pool. |
|
Min/Max Number of Threads for returning Busy Errors |
|
|
|
ns/servers/$server via
ns_pools and AM-modified pools.tcl but really
process-wide |
MinBusyThreads
MaxBusyThreads |
0
10 |
|
These
settings existed in AOLserver 2.x and were removed
in 3.x - 4.0 as those versions did not support
returning busy errors (they just let the OS backlog
and then refuse connnections). The
functionality is back in AOLserver 4.5 via the error
pool and limits.
These settings are implemented by AM-modified
pools.tcl by calling ns_pools set error -minthreads
and -maxthreads. Note
that in 2.x, you could set MaxBusyThreads to 0 and
the waiting queue (as well as the entire busy error
response mechanism) would be disabled.
This does not appear to be possible in 4.5.
To emulate the functionality, set MaxSock
(see below) to the same value as MaxThreads and then
the driver will simply never accept enough
connections to let them queue up and wait. |
|
Idle Thread Timeout |
ns/servers/$server AND
ns/servers/$server/pool/$pool |
threadtimeout |
120 |
ns/servers/$server via
ns_pools and pools.tcl but really process-wide |
threadtimeout |
0 |
|
In prior
versions of AOLserver, this was strictly per virtual
server. In AOLserver 4.0 and later,
there is the concept of separate connection thread
pools for certain mapped URLs, so this can be
configured either at the server level for the
default pool or for a specific pool.
Idle connection threads will be destroyed after this
timeout (in seconds). In the past a
setting of 0 was unsupported and under Windows
having threads with tcl interpreters destroyed
causes instability in AOLserver 3.2 - 4.0 and
substantial leaking of memory in AOLserver 4.5, so
we typically have this set to 1000000.
Note that C-level default in
AOLserver 4.5 is still 120 seconds but pools.tcl
from 4.5.1 overrides this and sets the default to 0
for the default thread pool but not for the error
thread pool.
AM-modified
pools.tcl applies this setting to both the default
and error thread pools for consistency. |
|
Maximum Number of Serviced Connections per Thread |
ns/servers/$server AND
ns/servers/$server/pool/$pool |
connsperthread |
0 |
ns/servers/$server via
ns_pools and pools.tcl but really process-wide |
maxconnections but
should be maxconns |
0 |
|
In prior
versions of AOLserver, this was strictly per virtual
server. In AOLserver 4.0 and later,
there is the concept of separate connection thread
pools for certain mapped URLs, so this can be
configured either at the server level for the
default pool or for a specific pool.
This is one of two most
mis-documented and mis-treated configuration
parameters in AOLserver (the other is
MaxConnections)! It does NOT mean how
many conns a single thread can have at the same
time. Instead, it specifies that after
the specified number of serviced connections, a
connection thread will be destroyed. This parameter
is useful for working around memory leaks in Tcl
code in theory but on Windows, thread destruction
causes instability in AOLserver 3.2 - 4.0 and
substantial leaking of memory in AOLserver 4.5, so
we never use this setting.
In AOLserver 4.5, the creation of the default
pool with various thread configuration parameters
was moved from server.c to pools.tcl.
Initial revision of
pools.tcl used a maxconns parameter which wasn't
backward compatible but at least made sense because
it matched the ns_pools -maxconns option.
Since revision 1.2 pools.tcl incorrectly uses
maxconnections for supposed backward compability,
only maxconnections means something totally else
(see below).
AM-modified pool.tcl uses
maxconns but falls back to ConnsPerThread for
backward compatibility.
|
|
Maximum Number of Driver Sockets/Connections |
ns/servers/$server AND
ns/servers/$server/pool/$pool |
maxconnections |
100 |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
maxsock |
100 |
|
In prior
versions of AOLserver, this was strictly per virtual
server. In AOLserver 4.0, this can be
configured either at the server level for the
default connection thread pool or for a specific
pool. This is one
of two most mis-documented and mis-treated
configuration parameters in AOLserver (the other is
ConnsPerThread)! It does NOT mean how
many connections a thread can service before
exiting. Instead, it serves to
pre-allocate the specified quantity of Conn
structures in AOLserver 4.0 and earlier and Sock
structures in AOLserver 4.5 and thus specifies the
upper bound of concurrent threads in the entire
virtual server (pre-4.0), pool (4.0), or for the
particular driver (4.5).
In general, this should be equal to at least
the sum of all the maxthread settings of all your
pools. To make it clear,
MaxConnections parameter no longer exists in 4.5 and
the ns_pools -maxconns option is equivalent to
ConnsPerThread, not MaxConnections.
|
|
Listen BackLog |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
backlog |
5 |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
backlog |
5 |
|
The
maximum number of connections waiting to be
serviced. The operating system will refuse any
additional connections. This waiting
number is over and above the maximum number of
concurrent connections being serviced or waiting to
be serviced by AOLserver (see above).
Set this and MaxBusyThreads to zero if you want
immediate refusal of excessive connections, which
may result in a faster failover to an alternate
server. Note that
there is also a listenbacklog parameter in
ns/parameters with a default of 32 but it's
overriden by the driver-level backlog or its
default. |
|
Keepalive Timeout |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
keepwait |
30 |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
keepwait |
30 |
|
Number of
seconds after which to hang up on clients while
waiting for an HTTP request in a connection:
keep-alive situation. |
|
Socket Timeout |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
socktimeout |
30 |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
socktimeout |
30 |
|
Number of seconds to
wait for an HTTP request before closing the
connection. Increase this to 5 minutes
to allow large files to be successfully uploaded. |
|
|
|
Maximum Size of data sent from the Browser |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
maxinput |
1 MB |
ns_limits
(or nssock
maxinput via AM-modified pool.tcl) |
maxupload |
10 MB |
|
This
setting is new to AOLserver 4.0 - any data in excess
of this size (in bytes) is refused (reportedly
browser keeps spinning and the connection never
completes - see SF Bug # 1008853). In
AOLserver 4.5, the driver maxinput setting only
specifies the maximum size before AOLserver starts
spooling additional content to a temporary file
(NaviServer has equivalent functionality with
parameter named maxupload, except it's ignored on
Windows) and the overall maximum size of uploaded
data is controlled with ns_limits maxupload option.
For backward
compatibility, AM-modified pools.tcl sets the
default -maxupload to the nssock maxinput parameter.
Currently, in
AOLserver 4.5.1 the temp file spooling does not work
on Windows. |
|
Maximum Amount of Data in a non multi-part form post |
ns/servers/$server |
maxpost |
256k |
|
|
|
|
The
maximum size in bytes of an HTTP POST accessed
through the Ns_ConnGetQuery function (in C) or the
ns_conn form function (in Tcl). This
setting no longer exists in AOLserver 4.5 or
NaviServer. It may have also been
non-functional in AOLserver 4.0 due to a bug in
driver.c. |
|
Maximum Amount of Data in request line & all headers |
ns/servers/$server |
maxheaders |
64k |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
maxheader |
32k |
|
The
maximum number of bytes for all HTTP header lines in
a request. Note that in
AOLserver 4.5, maxheader is now singular, not plural
but actually isn't used in connio.c
Ns_ConnReadHeaders, which uses maxline instead -
this may be a bug. |
|
Maximum Length of request or header line |
ns/servers/$server |
maxline |
16k |
ns/server/$server/module/nssock AND
ns/server/$server/module/nsopenssl
/ssldriver/nsopenssl |
maxline |
4k |
|
The maximum number of
bytes for the HTTP request or header line. |
file.