Struct wasmer_journal::concrete::compacting::SubGroupOfevents

struct SubGroupOfevents {
    events: Vec<usize>,
    path: Option<String>,
    write_map: HashMap<MemoryRange, usize>,
}

Subgroup of events that may or may not be retained in the final journal as it is compacted.

By grouping events into subevents it makes it possible to ignore an entire subgroup of events which are superseeded by a later event. For example, all the events involved in creating a file are irrelevant if that file is later deleted.

Fields

events: Vec<usize>

List of all the events that will be transferred over to the compacted journal if this sub group is selected to be carried over

path: Option<String>

The path metadata attached to this sub group of events is used to discard all subgroups related to a particular path of a file or directory. This is especially important if that file is later deleted and hence all the events related to it are no longer relevant

write_map: HashMap<MemoryRange, usize>

The write map allows the ccompacted to only keep the events relevant to the final outcome of a compacted journal rather than written regions that are later overridden. This is a crude write map that does not deal with overlapping writes (they still remain) However in the majority of cases this will remove duplicates while retaining a simple implementation

Trait Implementations

impl Debug for SubGroupOfevents

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for SubGroupOfevents

fn default() -> SubGroupOfevents

Returns the “default value” for a type.