NAME

dynamic_pager — dynamic pager external storage manager

SYNOPSIS

dynamic_pager [-E] [-F filename] [-S filesize] [-H high-water-trigger]
[-L low-water-trigger] [-P priority]

DESCRIPTION

The dynamic_pager daemon manages a pool of external swap files which the
kernel uses to support demand paging. This pool is expanded with new
swap files as load on the system increases, and contracted when the swap-
ping resources are no longer needed. The dynamic_pager daemon also pro-
vides a notification service for those applications which wish to receive
notices when the external paging pool expands or contracts.

OPTIONS

-E Encrypt the data in the swap files.

-F The base name of the filename to use for the external paging
files. By default this is /private/var/vm/swapfile.

-S The fixed filesize [in bytes] to use for the paging files. By
default dynamic_pager uses variable sized paging files, using
larger sized files as paging demands increase. The -S, -H and -L
options disable that default and cause dynamic_pager to use a
series of fixed sized external paging files.

-H If there are less than high-water-trigger bytes free in the
external paging files, the kernel will signal dynamic_pager to
add a new external paging file.

-L If there are more than low-water-trigger bytes free in the exter-
nal paging files, the kernel will coalese in-use pages and signal
dynamic_pager to discard an external paging file.
Low-water-trigger must be greater than high-water-trigger +
filesize.

-P This option is currently unimplemented.

FILES

/private/var/vm/swapfile* Default external paging files.

Next One

NAME

DirectoryService — DirectoryService daemon (a part of Mac OS X’s Open
Directory architecture)

SYNOPSIS

DirectoryService [-hv]

DESCRIPTION

Apple’s Open Directory architecture includes source code for both direc-
tory client access and directory servers. Open Directory forms the foun-
dation of how Mac OS X accesses all authoritative configuration informa-
tion (users, groups, mounts, managed desktop data, etc.). Mac OS X
obtains this information via abstraction APIs, enabling use of virtually
any directory system. Configuration of Open Directory is done through
the Directory Access applications in /Applications/Utilities. This
application can configure plugin settings, including turning on/off vari-
ous directory services.

Open Directory Access

Directory Services is a core part of the Open Directory technology.
Directory Services provides a client read/write/authentication API
abstraction for accessing directory-based data. Directory Services con-
sists of an access API, and an API daemon, and a plug-in API.

An additional element of Open Directory is the existing Darwin component
of lookupd that provides a read-only abstraction for accessing all BSD
configuration information. Both lookupd and Directory Services work in
conjunction with each other via the DSAgent to provide authoritative and
consistent configuration information to all processes running on Mac OS X
regardless of which Directory API they are using. The source code for
DSAgent is also available.

More information can be accessed from the Darwin Open Directory Page:
http://developer.apple.com/darwin/projects/opendirectory/

Open Directory Servers

Apple’s Open Directory Servers are OpenLDAP and NetInfo. OpenLDAP and
NetInfo are included as part of Mac OS X Desktop and Server, and are also
included with Darwin. Both OpenLDAP and NetInfo provide a robust and
scalable platform for serving directory based configuration information
for both stand-alone and networked CPUs. OpenLDAP and NetInfo share the
same datastore and both separately consist of:

o Access API
o Server process
o Command line tools for displaying and modifying the contents of the Directory Server data.

Documentation

Directory Services Access API and Plug-in API is documented at:
http://developer.apple.com/techpubs/macosx/Networking/

The headers for the DirectoryService APIs can also be found in the fol-
lowing location:

/System/Library/Frameworks/DirectoryService.framework/Headers/

OPTIONS

The options are as follows:

-h Display list of options
-v Display the release version.

PLUGINS

The following plugins can be managed using the Directory Access applica-
tion.

o BSD (Flat File and NIS)
o NetInfo
o LDAPv3
o Search
o SMB
o SLP
o Bonjour (zero-conf)
o Appletalk
o PasswordServer

DIAGNOSTICS

There are two helpful signals you can send to the DirectoryService daemon
to help diagnose problems you may be having. (Example: % sudo killall
-USR1 DirectoryService). USR2 logging automatically turns off after 5
minutes.

o USR1 Turns Debug Logging (on/off) See /Library/Logs/DirectoryService/DirectoryService.debug.log
o USR2 Turns API Logging (on/off) See /var/log/system.log