Google Linux servers hit with $5m patent infringement verdict (The Register) [LWN.net]

Google Linux servers hit with $5m patent infringement verdict (The Register)

Posted Apr 23, 2011 13:38 UTC (Sat) by Ad (guest, #74506)
In reply to: Google Linux servers hit with $5m patent infringement verdict (The Register) by orcmid
Parent article: Google Linux servers hit with $5m patent infringement verdict (The Register)

Most of the cache associated network (DNS cache, HTTP server and may be browser) has expiry time associated with each entry. The key, value map in cache can also use hashing.

Also network programs using asynchronous IO typically has only one thread. Tasks (including GC) can be done only when processing events. No separate GC thread, no separate GC pass.

So if a cache implements a mechanism where, while inserting entry, iterates and also cleans up expired entries, does that count as violation of this patent?

Just curious.

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Google Linux servers hit with $5m patent infringement verdict (The Register)

Posted Apr 23, 2011 18:01 UTC (Sat) by orcmid (guest, #74478) [Link]

I cannot respond to whether or not some speculative implementation would be an infringement.

Note, however, that the essential claims of '120 all involve the access to a linked list of same-hash records as part of the by-key record access mechanism and cleaning out at least some of the expired records on that list while doing so.

You should consult the text of U.S. Patent 5,893,120 to satisfy yourself one way or the other. It is found at http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&...

Also, you will need to look at the TIFF images for the code, flowcharts, and especially for the modifications made to the claims as part of a reexamination amendment that was issued on 2011-04-12. (The reexamination determination is on the last page. It modifies 4 of the 8 claims and adds 4 more.)