Using the minimum modification timestamp improve the checkpoint algorithm.

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    • Type: Improvement
    • Resolution: Gone away
    • Priority: Major - P3
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    • Affects Version/s: None
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    • 3

      Checkpoint can probably be made more efficient using the minimum modification timestamp, by using that value to determine if checkpoint is required to visit a page.

      If the minimum modification timestamp is less than the stable timestamp then checkpoint should visit the page, otherwise it shouldn't.

      I believe the relevant check is in bt_sync.c around line 246.

      /*
 * Skip clean pages, but need to make sure maximum transaction ID is always updated.
 */
if (!__wt_page_is_modified(walk->page)) {
    if (((mod = walk->page->modify) != NULL) && mod->rec_max_txn > btree->rec_max_txn)
        btree->rec_max_txn = mod->rec_max_txn;
    if (mod != NULL && btree->rec_max_timestamp < mod->rec_max_timestamp)
        btree->rec_max_timestamp = mod->rec_max_timestamp;
    continue;
}

       

            Assignee:
            Luke Pearson
            Reporter:
            Luke Pearson
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              Created:
              Updated:
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