ulex: thorny evergreen shrubs, also known as furze or gorse.
Your application needs a database but the moment you build in
dependence on Postgresql or Mysql your application becomes ponderous.
Ulex is a mesh networked sqlite3 database, intended to provide a
nimble alternative. It is designed so that nodes can come and go while
talking to each other and sharing data via sqlite3 in a (mostly) ACID
compliant way. Ulex mitigates issues with Sqlite3 on networked
filesystems (e.g. NFS, Moosefs etc.) such as "lock storms" (*) and
performance bottlenecks.
(*) Network filesystems must provide posix locking across all files
across all clients. This is handled by the file server by a queue. If
the queue gets overwhelmed by lock requests locks may be dropped. This
leads to concurrent access to shared files and in the case of sqlite3
the dreaded "database locked" message that won't go away (to fix you
have to move the file and copy it back). It can also lead to a
corrupted database.
About the name Ulex: The Ulex plant, also known as Gorse, furze, or
Whin, is considered an invasive pest in places like New Zealand but in
spite of its thorny persistence it is considered quite useful in its
native Europe, providing edible flowers, shelter and food for
wildlife, hedges and fuel for cooking.
