ISC DHCP 3.1.0a2 is now available!

David W. Hankins David_Hankins at
Wed Dec 13 20:04:37 UTC 2006

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ISC DHCP 3.1.0a2 is now available for download.  3.1.0 represents a
feature release, and contains many new features.  This second ALPHA
release fixes a few bugs, and adjusts the behaviour of a few features.

Most notable among the changes is a second pass at resizing the server's
internal hash tables.  In 3.1.0a1, many ludicrously oversized hash tables
were downsized, resulting in a substantially lowered memory use.  In this
release, many of the already undersized hash tables have been upsized,
attempting to approach a zero sum inbetween.  The hope is that the server
will use the same amount of memory as any 3.0.x release, but acheive
better performance in some operations.

A list of all changes made since 3.1.0a1 has been appended to the end of
this message.  For a complete list of changes from any previous release,
please consult the RELNOTES file within the source distribution, or on
our website:

This release, and its OpenPGP-signatures are available now from:

ISC's Release Signing Key can be obtained at:

                        Changes since 3.1.0a1

- A bug in the FQDN universe that added FQDN codes to the NWIP universe's
  hash table was repaired.

- The servers now try harder to transmit pending binding updates when
  entering normal state.

- UPDREQ/UPDREQALL handling was optimized - it no longer dequeues and
  requeues all pending updates.  This should reduce the number of spurious
  'xid mismatch' log messages.

- An option definition referencing leak was fixed, which resulted in early
  termination of dhclient upon the renewal event.

- Some default hash table sizes were tweaked, some upwards, some downwards.
  3.1.0a1's tables resulted in a reduction in default server memory use.
  The new selected values provide more of a zero sum (increasing the size
  of tables likely to be populated, decreasing the size of tables unlikely).

- Lease structures appear in three spearate hashes: by IP address, by UID,
  and by hardware address.  One type of table was used for all three, and
  improvements to IP address hashing were applied to all three (so UID and
  hardware addresses were treated like 4-byte integers).  There are now two
  types of tables, and the uid/hw hashes use functions more appropriate
  to their needs.

- The max-lease-misbalance percentage no longer causes scheduled rebalance
  runs to be skipped: it still governs the schedule, but every scheduled
  run will attempt balance.

- A segfault bug in recursive encapsulation support has been corrected.

David W. Hankins	"If you don't do it right the first time,
Software Engineer		you'll just have to do it again."
Internet Systems Consortium, Inc.	-- Jack T. Hankins
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