diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp
index 3c5b394be..202134841 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/test_v3.cpp
@@ -109,6 +109,40 @@ TEST_F(CowTestV3, MaxOp) {
     ASSERT_EQ(reader.header_v3().op_count, 20);
 }
 
+TEST_F(CowTestV3, MaxOpSingleThreadCompression) {
+    CowOptions options;
+    options.op_count_max = 20;
+    options.num_compress_threads = 1;
+    options.compression_factor = 4096 * 8;
+    options.compression = "lz4";
+
+    auto writer = CreateCowWriter(3, options, GetCowFd());
+    ASSERT_TRUE(writer->AddZeroBlocks(1, 20));
+    std::string data = "This is some data, believe it";
+    data.resize(options.block_size, '\0');
+
+    ASSERT_FALSE(writer->AddRawBlocks(5, data.data(), data.size()));
+
+    ASSERT_TRUE(writer->Finalize());
+}
+
+TEST_F(CowTestV3, MaxOpMultiThreadCompression) {
+    CowOptions options;
+    options.op_count_max = 20;
+    options.num_compress_threads = 2;
+    options.compression_factor = 4096 * 8;
+    options.compression = "lz4";
+
+    auto writer = CreateCowWriter(3, options, GetCowFd());
+    ASSERT_TRUE(writer->AddZeroBlocks(1, 20));
+    std::string data = "This is some data, believe it";
+    data.resize(options.block_size, '\0');
+
+    ASSERT_FALSE(writer->AddRawBlocks(5, data.data(), data.size()));
+
+    ASSERT_TRUE(writer->Finalize());
+}
+
 TEST_F(CowTestV3, ZeroOp) {
     CowOptions options;
     options.op_count_max = 20;
diff --git a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
index 22e6f2cbc..1e3fee748 100644
--- a/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
+++ b/fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.cpp
@@ -356,6 +356,9 @@ bool CowWriterV3::ConstructCowOpCompressedBuffers(uint64_t new_block_start, cons
                    << ", actual number of blocks received from compressor " << blocks.size();
         return false;
     }
+    if (!CheckOpCount(blocks.size())) {
+        return false;
+    }
     size_t blocks_written = 0;
     for (size_t blk_index = 0; blk_index < blocks.size(); blk_index++) {
         CowOperation& op = cached_ops_.emplace_back();
@@ -395,9 +398,6 @@ bool CowWriterV3::EmitBlocks(uint64_t new_block_start, const void* data, size_t
     }
     const auto bytes = reinterpret_cast<const uint8_t*>(data);
     const size_t num_blocks = (size / header_.block_size);
-    if (!CheckOpCount(num_blocks)) {
-        return false;
-    }
     for (size_t i = 0; i < num_blocks;) {
         const size_t blocks_to_write =
                 std::min<size_t>(batch_size_ - cached_data_.size(), num_blocks - i);