Can Berkeley DB use NFS, SAN, or other remote/shared/network filesystems for databases and their environments?
This is a tricky question. The answer isn’t as obvious as you might think. Berkeley DB works great with a SAN (and with any other filesystem type as far as we know), but if you attempt to access any filesystem from multiple machines, you are treating the filesystem as a shared, remote filesystem and this can cause problems for Berkeley DB. See the “Remote filesystems” section of the Berkeley DB Reference Guide for more information. There are two problems with shared/remote filesystems, mutexes and cache consistency.
Berkeley DB works great with a SAN (and with any other filesystem type as far as we know), but if you attempt to access any filesystem from multiple machines, you are treating the filesystem as a shared, remote filesystem and this can cause problems for Berkeley DB. See the “Remote filesystems” section of the Berkeley DB Reference Guide for more information.There are two problems with shared/remote filesystems, mutexes and cache consistency.First, mutexes: For remote filesystems that do allow remote files to be mapped into process memory, database environment directories accessed via remote filesystems cannot be used simultaneously from multiple clients (that is, from multiple computers). No commercial remote filesystem of which we’re aware supports coherent, distributed shared memory for remote-mounted files. As a result, different machines will see different versions of these shared region files, and the behavior is undefined. For example, if machine A opens a database environment on
Berkeley DB works great with a SAN (and with any other filesystem type as far as we know), but if you attempt to access any filesystem from multiple machines, you are treating the filesystem as a shared, remote filesystem and this can cause problems for Berkeley DB. See the “Remote filesystems” section of the Berkeley DB Reference Guide for more information. There are two problems with shared/remote filesystems, mutexes and cache consistency. First, mutexes: For remote filesystems that do allow remote files to be mapped into process memory, database environment directories accessed via remote filesystems cannot be used simultaneously from multiple clients (that is, from multiple computers). No commercial remote filesystem of which we’re aware supports coherent, distributed shared memory for remote-mounted files. As a result, different machines will see different versions of these shared region files, and the behavior is undefined. For example, if machine A opens a database environment
Berkeley DB works great with a SAN (and with any other filesystem type as far as we know), but if you attempt to access any filesystem from multiple machines, you are treating the filesystem as a shared, remote filesystem and this can cause problems for Berkeley DB. See the Remote filesystems section of the Berkeley DB Reference Guide for more information. There are two problems with shared/remote filesystems, mutexes and cache consistency. First, mutexes: For remote filesystems that do allow remote files to be mapped into process memory, database environment directories accessed via remote filesystems cannot be used simultaneously from multiple clients (that is, from multiple computers). No commercial remote filesystem of which we’re aware supports coherent, distributed shared memory for remote-mounted files. As a result, different machines will see different versions of these shared region files, and the behavior is undefined. For example, if machine A opens a database environment on
Related Questions
- Why don’t Berkeley DB and Berkeley DB Java Edition both implement a shared set of Java interfaces for the API? Why are these two similar APIs in different Java packages?
- Why am I getting "Berkeley DB library configured to support only DB_PRIVATE environments" or "Berkeley DB library configured to support only private environments"?
- Can Berkeley DB use NFS, SAN, or other remote/shared/network filesystems for databases and their environments?
