Struct swap::page_handler::TrimContext

pub struct TrimContext<'a> {
    ctx: &'a Mutex<PageHandleContext<'a>>,
    cur_region: usize,
    cur_page: usize,
    next_data_in_file: Range<usize>,
    clean_pages: usize,
    zero_pages: usize,
}

Context for trim operation.

This drops 2 types of pages in the staging memory to reduce disk write.

• Clean pages
  • The pages which have been swapped out to the disk and have not been changed.
  • Drop the pages in the staging memory and mark it as present on the swap file.
• Zero pages
  • Drop the pages in the staging memory. The pages will be UFFD_ZEROed on page fault.

Fields

ctx: &'a Mutex<PageHandleContext<'a>>

cur_region: usize

cur_page: usize

next_data_in_file: Range<usize>

The page idx range of pages which have been stored in the swap file.

clean_pages: usize

zero_pages: usize

Implementations

impl TrimContext<'_>

pub fn trim_pages(&mut self, max_pages: usize) -> Result<Option<usize>>

Trim pages in the staging memory.

This returns the pages trimmed. This returns None if it traversed all pages in the staging memory.

Arguments

max_size - The maximum pages to be compared.

pub fn trimmed_clean_pages(&self) -> usize

Total trimmed clean pages.

pub fn trimmed_zero_pages(&self) -> usize

Total trimmed zero pages.