Pgpgin|pgpgout|pswpin|pswpout Meaning and Difference

Pgpgin|pgpgout|pswpin|pswpout Meaning and Difference

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The main meaning of the article is:

1. Page in/out action refers to reading the pages in a block device into memory or writing a page in memory to a block device

When the ever program or the data needs to being accessed and is the read in from the IT permanent location on disk, the is called a page I N Request. When the ever program or the data needs to be saved and are written to a permanent location on disk, this is the called a page out requ Est.

2. Pages in page In/out refer to disk sector, size 512 bytes instead of 4k size pages in virtual memory

The kernel tracks each disk page (512b) of read in within the Pgpgin (pages paged in) counter

3. Pgpgin/pgpgout refers to the number of page in/out between main memory and block device (hard disk).

These counters is related to virtual memory "paging" only in the fact that they is doing disk IO to load a memory page W ITH data from disk or write the data from a memory page back to disk

4. Pswpin/pswpout refers to the number of pages in virtual memory that are read/read from the swap area of the block device. Therefore, it is included in the Pgpgin/pgpgout.

Pages swapped in or out be also counted within pages paged in or out respectively since swap Io is still ultimately block Device based.

Pgpgin|pgpgout|pswpin|pswpout Meaning and Difference