From 08d75b91e56c2b6cf340a3ff9277d98cd9b5713c Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Thu, 28 Dec 2023 10:14:18 +0100 Subject: [PATCH] librbd: propagate diff-iterate range to parent in fast-diff mode When getting parent diff, pass the overlap-reduced image extent instead of the entire 0..overlap range to avoid a similar quadratic slowdown on cloned images. Signed-off-by: Ilya Dryomov (cherry picked from commit 7677d4b1b52ab68484545d0fcd7348f2f8e9f263) --- src/librbd/api/DiffIterate.cc | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/src/librbd/api/DiffIterate.cc b/src/librbd/api/DiffIterate.cc index a464b942ae091..b114c32fabad0 100644 --- a/src/librbd/api/DiffIterate.cc +++ b/src/librbd/api/DiffIterate.cc @@ -293,12 +293,14 @@ int DiffIterate::execute() { std::shared_lock image_locker{m_image_ctx.image_lock}; uint64_t raw_overlap = 0; m_image_ctx.get_parent_overlap(m_image_ctx.snap_id, &raw_overlap); - auto overlap = m_image_ctx.reduce_parent_overlap(raw_overlap, false); - if (overlap.first > 0 && overlap.second == io::ImageArea::DATA) { + io::Extents parent_extents = {{m_offset, m_length}}; + if (m_image_ctx.prune_parent_extents(parent_extents, io::ImageArea::DATA, + raw_overlap, false) > 0) { ldout(cct, 10) << " first getting parent diff" << dendl; - DiffIterate diff_parent(*m_image_ctx.parent, {}, nullptr, 0, - overlap.first, true, true, &simple_diff_cb, - &parent_diff); + DiffIterate diff_parent(*m_image_ctx.parent, {}, nullptr, + parent_extents[0].first, + parent_extents[0].second, true, true, + &simple_diff_cb, &parent_diff); r = diff_parent.execute(); if (r < 0) { return r; -- 2.39.5