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.Dd December 17, 2013
.Dt CK_HS_GC 3
.Sh NAME
.Nm ck_hs_gc
.Nd perform maintenance on a hash set
.Sh LIBRARY
Concurrency Kit (libck, \-lck)
.Sh SYNOPSIS
.In ck_hs.h
.Ft bool
.Fn ck_hs_gc "ck_hs_t *hs" "unsigned long cycles" "unsigned long seed"
.Sh DESCRIPTION
The
.Fn ck_hs_gc 3
function will perform various maintenance routines on the hash set
pointed to by
.Fa hs ,
including defragmentation of probe sequences with respect to tombstones
and in the case that the delete workload hint has been passed, recalculation
of probe sequence bounds. The
.Fa cycles
argument is used to indicate how many hash set entries should be subject
to attempted maintenance. If
.Fa cycles
is 0, then maintenance is performed on the complete hash set. The
.Fa seed
argument determines the start location of the maintenance process. If
.Fa cycles
is non-zero, it is recommended that
.Fa seed
is some random value. If the delete hint has been passed, the function
will require an additional 12% of memory (with respect to existing
memory usage of the set), until operation completion.
.Sh RETURN VALUES
Upon successful completion,
.Fn ck_hs_gc 3
returns true and otherwise returns false on failure due to memory allocation
failure.
.Sh ERRORS
This function will only return false if there are internal memory allocation
failures.
.Sh SEE ALSO
.Xr ck_hs_init 3 ,
.Xr ck_hs_move 3 ,
.Xr ck_hs_destroy 3 ,
.Xr CK_HS_HASH 3 ,
.Xr ck_hs_iterator_init 3 ,
.Xr ck_hs_next 3 ,
.Xr ck_hs_get 3 ,
.Xr ck_hs_put 3 ,
.Xr ck_hs_put_unique 3 ,
.Xr ck_hs_grow 3 ,
.Xr ck_hs_rebuild 3 ,
.Xr ck_hs_set 3 ,
.Xr ck_hs_fas 3 ,
.Xr ck_hs_remove 3 ,
.Xr ck_hs_count 3 ,
.Xr ck_hs_reset 3 ,
.Xr ck_hs_reset_size 3 ,
.Xr ck_hs_stat 3
.Pp
Additional information available at http://concurrencykit.org/
