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NSCD.CONF(5)		    BSD	File Formats Manual		  NSCD.CONF(5)

     nscd.conf -- nscd configuration file

     The nscd.conf file	is used	by the nscd(8) daemon and is read on its
     startup.  Its syntax is mostly similar to the nscd.conf syntax in Linux
     and Solaris.  It has some differences, though -- see them below.

     Each line specifies either	an attribute and a value, or an	attribute, a
     cachename and a value.  Usual cachenames are "passwd", "group", "hosts",
     "services", "protocols" and "rpc".	 You can also use any other cachename
     (for example, if some third-party application uses	nsswitch).

     threads [value]
	     Number of threads,	which would listen for connections and process
	     requests.	The minimum is 1.  The default value is	8.

     enable-cache [cachename] [yes | no]
	     Enables or	disables the cache for specified cachename.

     positive-time-to-live [cachename] [value]
	     Sets the TTL (time-to-live) for the specified cache in seconds.
	     Larger values can increase	system's performance, but they also
	     can affect	the cache coherence.  The default value	is 3600.

     positive-policy [cachename] [fifo | lru | lfu]
	     The policy	that is	applied	to erase some of the cache elements,
	     when the size limit of the	given cachename	is exceeded.  Possible
	     policies are: fifo	(first-in-first-out), lru (least-recently-
	     used), and	lfu (least-frequently-used).  The default policy is

     negative-time-to-live [cachename] [value]
	     The TTL of	the negative cached elements in	seconds.  The larger
	     values can	significantly increase system performance in some en-
	     vironments	(when dealing with files with UIDs, which are not in
	     system databases, for example).  This number should be kept low
	     to	avoid the cache	coherence problems.  The default value is 60.

     negative-policy [cachename] [fifo | lru | lfu]
	     The same as the positive-policy, but this one is applied to the
	     negative elements of the given cachename.	The default policy is

     negative-confidence-threshold [cachename] [value]
	     The number	of times a query must have failed before the cache ac-
	     cepts that	the element can	not be found.  At the default value of
	     1 each negative query result is cached and	immediately returned
	     from the cache on further queries.	 Higher	numbers	cause queries
	     to	be retried at the configured data sources the given number of
	     times, before the negative	result is returned from	the cache on
	     further queries.  This allows to probe for	the existence of an
	     entry, and	then to	create it if it	did not	exist, without the
	     negative probe result preventing access to	the new	entry for the
	     duration of the negative TTL.

     suggested-size [cachename]	[value]
	     This is the internal hash table size.  The	value should be	a
	     prime number for optimum performance.  You	should only change
	     this value	when the number	of cached elements is significantly
	     (5-10 times) greater than the default hash	table size (257).

     keep-hot-count [cachename]	[value]
	     The size limit of the cache with the given	cachename.  When it is
	     exceeded, the policy will be applied.  The	default	value is 2048.

     perform-actual-lookups [cachename]	[yes | no]
	     If	enabled, the nscd(8) does not simply receive and cache the
	     NSS-requests results, but performs	all the	lookups	by itself and
	     only returns the responses.  If this feature is enabled, then for
	     the given cachename nscd(8) will act similarly to the NSCD.

	     NOTE: this	feature	is currently experimental -- it	supports only
	     "passwd", "group" and "services" cachenames.

     You can use the `#' symbol	at the beginning of the	line for comments.



     Michael Bushkov <>

BSD				October	6, 2018				   BSD


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