Database Reference
In-Depth Information
*
Default cache_type
**
Only available in Neo4j Enterprise edition. (Note: this cache has successfully been used by some customers with
heap sizes of up to 200 GB.)
AsincreasingtheJVMheapsizeeatsintotheoverallRAMavailableonthebox,thesetting
of the heap size and the settings for the filesystem cache should really be considered to-
gether. Remember to include other factors as well, such as the OS's requirements for RAM
and any other processes that may be running on the box. If you're running in embedded
mode, the Neo4j database will be sharing the JVM heap with your host application, so en-
sure that this is catered to as well!
Caching summary
Your caching approach can be summarized as follows:
• At a minimum, aim for a setup that allows for all, or as much as possible, of the
graph to fit into the filesystem cache.
• Thereafter, make as much use of the object cache as feasible.
11.1.5. Transaction logs and recoverability
Shifting to the right side of our high-level architecture diagram (see
figure 11.3
), we'll fo-
cus on providing a brief overview of how the transaction log files (sometimes also referred
to as the
logical files
), are used to ensure Neo4j is ACID-compliant. But more importantly
forthis chapter,we'll look at how the transaction logs are used to promote self-healing and
recoverability.
