diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index 08a79ba..d102863 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -826,6 +826,9 @@
     bool DeleteDeviceIfExists(const std::string& name,
                               const std::chrono::milliseconds& timeout_ms = {});
 
+    // Set read-ahead size during OTA
+    void SetReadAheadSize(const std::string& entry_block_device, off64_t size_kb);
+
     android::dm::IDeviceMapper& dm_;
     std::unique_ptr<IDeviceInfo> device_;
     std::string metadata_dir_;
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index e91e3b7..81f396a 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -30,6 +30,7 @@
 #include <android-base/logging.h>
 #include <android-base/parseint.h>
 #include <android-base/properties.h>
+#include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>
 #include <cutils/sockets.h>
@@ -82,12 +83,28 @@
 using std::chrono::duration_cast;
 using namespace std::chrono_literals;
 using namespace std::string_literals;
+using android::base::Realpath;
+using android::base::StringPrintf;
 
 static constexpr char kBootSnapshotsWithoutSlotSwitch[] =
         "/metadata/ota/snapshot-boot-without-slot-switch";
 static constexpr char kBootIndicatorPath[] = "/metadata/ota/snapshot-boot";
 static constexpr char kRollbackIndicatorPath[] = "/metadata/ota/rollback-indicator";
 static constexpr auto kUpdateStateCheckInterval = 2s;
+/*
+ * The readahead size is set to 32kb so that
+ * there is no significant memory pressure (/proc/pressure/memory) during boot.
+ * After OTA, during boot, partitions are scanned before marking slot as successful.
+ * This scan will trigger readahead both on source and COW block device thereby
+ * leading to Inactive(file) pages to be very high.
+ *
+ * A lower value may help reduce memory pressure further, however, that will
+ * increase the boot time. Thus, for device which don't care about OTA boot
+ * time, they could use O_DIRECT functionality wherein the I/O to the source
+ * block device will be O_DIRECT.
+ */
+static constexpr auto kCowReadAheadSizeKb = 32;
+static constexpr auto kSourceReadAheadSizeKb = 32;
 
 // Note: IImageManager is an incomplete type in the header, so the default
 // destructor doesn't work.
@@ -1748,6 +1765,9 @@
                 snapuserd_argv->emplace_back(std::move(message));
             }
 
+            SetReadAheadSize(cow_image_device, kCowReadAheadSizeKb);
+            SetReadAheadSize(source_device, kSourceReadAheadSizeKb);
+
             // Do not attempt to connect to the new snapuserd yet, it hasn't
             // been started. We do however want to wait for the misc device
             // to have been created.
@@ -4404,5 +4424,31 @@
     return true;
 }
 
+void SnapshotManager::SetReadAheadSize(const std::string& entry_block_device, off64_t size_kb) {
+    std::string block_device;
+    if (!Realpath(entry_block_device, &block_device)) {
+        PLOG(ERROR) << "Failed to realpath " << entry_block_device;
+        return;
+    }
+
+    static constexpr std::string_view kDevBlockPrefix("/dev/block/");
+    if (!android::base::StartsWith(block_device, kDevBlockPrefix)) {
+        LOG(ERROR) << block_device << " is not a block device";
+        return;
+    }
+
+    std::string block_name = block_device.substr(kDevBlockPrefix.length());
+    std::string sys_partition =
+            android::base::StringPrintf("/sys/class/block/%s/partition", block_name.c_str());
+    struct stat info;
+    if (lstat(sys_partition.c_str(), &info) == 0) {
+        block_name += "/..";
+    }
+    std::string sys_ra = android::base::StringPrintf("/sys/class/block/%s/queue/read_ahead_kb",
+                                                     block_name.c_str());
+    std::string size = std::to_string(size_kb);
+    android::base::WriteStringToFile(size, sys_ra.c_str());
+}
+
 }  // namespace snapshot
 }  // namespace android
diff --git a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h
index d07d2f8..7c99085 100644
--- a/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h
+++ b/fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_verify.h
@@ -48,10 +48,27 @@
     std::mutex m_lock_;
     std::condition_variable m_cv_;
 
+    /*
+     * Scanning of partitions is an expensive operation both in terms of memory
+     * and CPU usage. The goal here is to scan the partitions fast enough without
+     * significant increase in the boot time.
+     *
+     * Partitions such as system, product which may be huge and may need multiple
+     * threads to speed up the verification process. Using multiple threads for
+     * all partitions may increase CPU usage significantly. Hence, limit that to
+     * 1 thread per partition.
+     *
+     * These numbers were derived by monitoring the memory and CPU pressure
+     * (/proc/pressure/{cpu,memory}; and monitoring the Inactive(file) and
+     * Active(file) pages from /proc/meminfo.
+     *
+     * Additionally, for low memory devices, it is advisible to use O_DIRECT
+     * fucntionality for source block device.
+     */
     int kMinThreadsToVerify = 1;
-    int kMaxThreadsToVerify = 4;
-    uint64_t kThresholdSize = 512_MiB;
-    uint64_t kBlockSizeVerify = 1_MiB;
+    int kMaxThreadsToVerify = 3;
+    uint64_t kThresholdSize = 750_MiB;
+    uint64_t kBlockSizeVerify = 2_MiB;
 
     bool IsBlockAligned(uint64_t read_size) { return ((read_size & (BLOCK_SZ - 1)) == 0); }
     void UpdatePartitionVerificationState(UpdateVerifyState state);