From 415d570cf2f404ef560f5d6a5af73653e1ec6204 Mon Sep 17 00:00:00 2001
From: Marcus Holland-Moritz <github@mhxnet.de>
Date: Fri, 28 Mar 2025 22:30:54 +0100
Subject: [PATCH] fix(block_cache): don't prefetch blocks that are in the
 active list

---
 src/reader/internal/block_cache.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/reader/internal/block_cache.cpp b/src/reader/internal/block_cache.cpp
index daaaba73..8d7bbf36 100644
--- a/src/reader/internal/block_cache.cpp
+++ b/src/reader/internal/block_cache.cpp
@@ -383,7 +383,8 @@ class block_cache_ final : public block_cache::impl {
       if (auto next = seq_access_detector_->prefetch()) {
         std::lock_guard lock(mx_);
 
-        if (cache_.findWithoutPromotion(*next) == cache_.end()) {
+        if (cache_.findWithoutPromotion(*next) == cache_.end() &&
+            active_.find(*next) == active_.end()) {
           sequential_prefetches_.fetch_add(1, std::memory_order_relaxed);
           create_cached_block(*next, std::promise<block_range>{}, 0,
                               std::numeric_limits<size_t>::max());