Crate pagecache

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Expand description

pagecache is a lock-free pagecache and log for building high-performance databases.


pub use self::logger::Log;
pub use self::logger::LogRead;


Working with Log


A finalized ConfigBuilder that can be use multiple times to open a Tree or Log.
Top-level configuration for the system.
A guard that keeps the current thread pinned.
A metric collector for all pagecache users running in this process.
A materializer for things that have nothing to materialize or recover, like a standalone Log.
A lock-free pagecache which supports fragmented pages for dramatically improving write throughput.
A pointer to shared lock-free state bound by a pinned epoch’s lifetime.
A pending log reservation which can be aborted or completed. NB the holder should quickly call complete or abort as taking too long to decide will cause the underlying IO buffer to become blocked.
A handle to an ongoing pagecache transaction. Ensures that any state which is removed from a shared in-memory data structure is not destroyed until all possible readers have concluded.


Points to either a memory location or a disk location to page-in data from.
A pointer to a location on disk or an off-log blob.
An Error type encapsulating various issues that may come up in both the expected and unexpected operation of a PageCache.
The result of a get call in the PageCache.
The log may be configured to write data in several different ways, depending on the constraints of the system using it.


A user of a PageCache needs to provide a Materializer which handles the merging of page fragments.


This function is useful for inducing random jitter into our atomic operations, shaking out more possible interleavings quickly. It gets fully elliminated by the compiler in non-test code.
Pins the current thread.
Returns a reference to a dummy guard that allows unprotected access to Atomics.

Type Definitions

A pointer to an blob blob.
A log file offset.
A logical sequence number.
Allows arbitrary logic to be injected into mere operations of the PageCache.
A page identifier.
The top-level result type for dealing with the PageCache.
An offset for a storage file segment.