The Squid HTTP Proxy team is very pleased to announce the availability
of the Squid-4.0.15 release!
This release is a bug fix and stability release resolving several issues
found in the prior Squid releases.
The major changes to be aware of:
This release there are no major changes. Despite the size of code
commited most of the change has been small polishing and stability
changes. Some incidental and minor memory leaks have been resolved, and
some crashes introduced by the new Squid-4 features have been resolved.
One change shared with 3.5.22 is noteworthy as it affects cache storage
* Bug #4471: revalidation doesn't work when expired cached object lacks
Historically Squid used only Last-Modified header value for evaluating
entry's last modification time while making an internal revalidation
requests. So, without Last-Modified it was not possible to correctly
fill the If-Modified-Since header value. Which would result in many
unnecessary MISS. This release now uses Date header to synthesize a
Last-Modified value if none is provided.
This change affects a binary difference in all cache objects stored by
Squid-4.0.15 or later, and by Squid-3.5.22 or later.
* When upgrading, older cache content is handled automatically.
* When downgrading for any reason to an older version the cache will
need to be erased and rebuilt from empty to remove those new objects.
All users of Squid-4.0.x are encouraged to upgrade to this release as
soon as possible.
All users of Squid-3 are encouraged to test this release out and plan
for upgrades where possible.
See the ChangeLog for the full list of changes in this and earlier
Please refer to the release notes at
when you are ready to make the switch to Squid-4
This new release can be downloaded from our HTTP or FTP servers
or the mirrors. For a list of mirror sites see
If you encounter any issues with this release please file a bug report.
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