Add lz4 support for VABC
Add lz4 support in CowWriter/CowReader. Lz4 should offer faster
read/write performance but slightly larger COW sizes.
Download time: Reduced from 1264s to 825s (~35% faster)
Filesystem verification time: from 69s to 59s (~15% faster)
COW Size: 2.59GB to 3.21GB, (~25% regression)
Merge time: 37046ms to 27690ms (~25% faster)
Boot time: LZ4 is 2.7% faster
Overall, LZ4 offers faster read/write performance at the cost of 25%
space regression.
Test: th
Bug: 228478555
Change-Id: Ie521852fb3c9ff8a12e55b764c1eb1838f7b2181
diff --git a/fastboot/Android.bp b/fastboot/Android.bp
index 5c07eb0..22665ed 100644
--- a/fastboot/Android.bp
+++ b/fastboot/Android.bp
@@ -190,6 +190,7 @@
"libhealthhalutils",
"libhealthshim",
"libsnapshot_cow",
+ "liblz4",
"libsnapshot_nobinder",
"update_metadata-protos",
],
@@ -254,6 +255,7 @@
"libsparse",
"libutils",
"liblog",
+ "liblz4",
"libz",
"libdiagnose_usb",
"libbase",
diff --git a/fs_mgr/libsnapshot/Android.bp b/fs_mgr/libsnapshot/Android.bp
index 6db8f13..dffb2e7 100644
--- a/fs_mgr/libsnapshot/Android.bp
+++ b/fs_mgr/libsnapshot/Android.bp
@@ -44,7 +44,6 @@
"libext2_uuid",
"libext4_utils",
"libfstab",
- "libsnapshot_cow",
"libsnapshot_snapuserd",
"libz",
],
@@ -154,22 +153,6 @@
"-Wall",
"-Werror",
],
- export_include_dirs: ["include"],
- srcs: [
- "cow_decompress.cpp",
- "cow_reader.cpp",
- "cow_writer.cpp",
- "cow_format.cpp",
- ],
-}
-
-cc_library_static {
- name: "libsnapshot_cow",
- defaults: [
- "libsnapshot_cow_defaults",
- ],
- host_supported: true,
- recovery_available: true,
shared_libs: [
"libbase",
"liblog",
@@ -177,7 +160,24 @@
static_libs: [
"libbrotli",
"libz",
+ "liblz4",
],
+ export_include_dirs: ["include"],
+}
+
+cc_library_static {
+ name: "libsnapshot_cow",
+ defaults: [
+ "libsnapshot_cow_defaults",
+ ],
+ srcs: [
+ "cow_decompress.cpp",
+ "cow_reader.cpp",
+ "cow_writer.cpp",
+ "cow_format.cpp",
+ ],
+ host_supported: true,
+ recovery_available: true,
ramdisk_available: true,
vendor_ramdisk_available: true,
}
@@ -214,7 +214,7 @@
cc_defaults {
name: "libsnapshot_test_defaults",
- defaults: ["libsnapshot_defaults"],
+ defaults: ["libsnapshot_defaults", "libsnapshot_cow_defaults"],
srcs: [
"partition_cow_creator_test.cpp",
"snapshot_metadata_updater_test.cpp",
@@ -295,6 +295,7 @@
cc_binary {
name: "snapshotctl",
+ defaults: ["libsnapshot_cow_defaults", "libsnapshot_hal_deps"],
srcs: [
"snapshotctl.cpp",
],
@@ -343,6 +344,9 @@
cc_defaults {
name: "libsnapshot_fuzzer_defaults",
+ defaults: [
+ "libsnapshot_cow_defaults",
+ ],
native_coverage : true,
srcs: [
// Compile the protobuf definition again with type full.
@@ -416,6 +420,7 @@
name: "cow_api_test",
defaults: [
"fs_mgr_defaults",
+ "libsnapshot_cow_defaults",
],
srcs: [
"cow_api_test.cpp",
@@ -471,6 +476,7 @@
"libsparse",
"libxz",
"libz",
+ "liblz4",
"libziparchive",
"update_metadata-protos",
],
@@ -486,6 +492,9 @@
cc_binary {
name: "estimate_cow_from_nonab_ota",
+ defaults: [
+ "libsnapshot_cow_defaults",
+ ],
host_supported: true,
device_supported: false,
cflags: [
@@ -519,6 +528,7 @@
name: "inspect_cow",
host_supported: true,
device_supported: true,
+ defaults: ["libsnapshot_cow_defaults"],
cflags: [
"-D_FILE_OFFSET_BITS=64",
"-Wall",
diff --git a/fs_mgr/libsnapshot/cow_decompress.cpp b/fs_mgr/libsnapshot/cow_decompress.cpp
index faceafe..a4d2277 100644
--- a/fs_mgr/libsnapshot/cow_decompress.cpp
+++ b/fs_mgr/libsnapshot/cow_decompress.cpp
@@ -20,6 +20,7 @@
#include <android-base/logging.h>
#include <brotli/decode.h>
+#include <lz4.h>
#include <zlib.h>
namespace android {
@@ -260,5 +261,43 @@
return std::unique_ptr<IDecompressor>(new BrotliDecompressor());
}
+class Lz4Decompressor final : public IDecompressor {
+ public:
+ ~Lz4Decompressor() override = default;
+
+ bool Decompress(const size_t output_size) override {
+ size_t actual_buffer_size = 0;
+ auto&& output_buffer = sink_->GetBuffer(output_size, &actual_buffer_size);
+ if (actual_buffer_size != output_size) {
+ LOG(ERROR) << "Failed to allocate buffer of size " << output_size << " only got "
+ << actual_buffer_size << " bytes";
+ return false;
+ }
+ std::string input_buffer;
+ input_buffer.resize(stream_->Size());
+ size_t bytes_read = 0;
+ stream_->Read(input_buffer.data(), input_buffer.size(), &bytes_read);
+ if (bytes_read != input_buffer.size()) {
+ LOG(ERROR) << "Failed to read all input at once. Expected: " << input_buffer.size()
+ << " actual: " << bytes_read;
+ return false;
+ }
+ const int bytes_decompressed =
+ LZ4_decompress_safe(input_buffer.data(), static_cast<char*>(output_buffer),
+ input_buffer.size(), output_size);
+ if (bytes_decompressed != output_size) {
+ LOG(ERROR) << "Failed to decompress LZ4 block, expected output size: " << output_size
+ << ", actual: " << bytes_decompressed;
+ return false;
+ }
+ sink_->ReturnData(output_buffer, output_size);
+ return true;
+ }
+};
+
+std::unique_ptr<IDecompressor> IDecompressor::Lz4() {
+ return std::make_unique<Lz4Decompressor>();
+}
+
} // namespace snapshot
} // namespace android
diff --git a/fs_mgr/libsnapshot/cow_decompress.h b/fs_mgr/libsnapshot/cow_decompress.h
index f485256..7f74eda 100644
--- a/fs_mgr/libsnapshot/cow_decompress.h
+++ b/fs_mgr/libsnapshot/cow_decompress.h
@@ -41,6 +41,7 @@
static std::unique_ptr<IDecompressor> Uncompressed();
static std::unique_ptr<IDecompressor> Gz();
static std::unique_ptr<IDecompressor> Brotli();
+ static std::unique_ptr<IDecompressor> Lz4();
// |output_bytes| is the expected total number of bytes to sink.
virtual bool Decompress(size_t output_bytes) = 0;
diff --git a/fs_mgr/libsnapshot/cow_reader.cpp b/fs_mgr/libsnapshot/cow_reader.cpp
index 746feeb..653492c 100644
--- a/fs_mgr/libsnapshot/cow_reader.cpp
+++ b/fs_mgr/libsnapshot/cow_reader.cpp
@@ -775,6 +775,9 @@
case kCowCompressBrotli:
decompressor = IDecompressor::Brotli();
break;
+ case kCowCompressLz4:
+ decompressor = IDecompressor::Lz4();
+ break;
default:
LOG(ERROR) << "Unknown compression type: " << op.compression;
return false;
diff --git a/fs_mgr/libsnapshot/cow_writer.cpp b/fs_mgr/libsnapshot/cow_writer.cpp
index 5ce1d3b..7281fc2 100644
--- a/fs_mgr/libsnapshot/cow_writer.cpp
+++ b/fs_mgr/libsnapshot/cow_writer.cpp
@@ -24,8 +24,10 @@
#include <android-base/logging.h>
#include <android-base/unique_fd.h>
#include <brotli/encode.h>
+#include <libsnapshot/cow_format.h>
#include <libsnapshot/cow_reader.h>
#include <libsnapshot/cow_writer.h>
+#include <lz4.h>
#include <zlib.h>
namespace android {
@@ -129,6 +131,8 @@
compression_ = kCowCompressGz;
} else if (options_.compression == "brotli") {
compression_ = kCowCompressBrotli;
+ } else if (options_.compression == "lz4") {
+ compression_ = kCowCompressLz4;
} else if (options_.compression == "none") {
compression_ = kCowCompressNone;
} else if (!options_.compression.empty()) {
@@ -403,35 +407,56 @@
std::basic_string<uint8_t> CowWriter::Compress(const void* data, size_t length) {
switch (compression_) {
case kCowCompressGz: {
- auto bound = compressBound(length);
- auto buffer = std::make_unique<uint8_t[]>(bound);
+ const auto bound = compressBound(length);
+ std::basic_string<uint8_t> buffer(bound, '\0');
uLongf dest_len = bound;
- auto rv = compress2(buffer.get(), &dest_len, reinterpret_cast<const Bytef*>(data),
+ auto rv = compress2(buffer.data(), &dest_len, reinterpret_cast<const Bytef*>(data),
length, Z_BEST_COMPRESSION);
if (rv != Z_OK) {
LOG(ERROR) << "compress2 returned: " << rv;
return {};
}
- return std::basic_string<uint8_t>(buffer.get(), dest_len);
+ buffer.resize(dest_len);
+ return buffer;
}
case kCowCompressBrotli: {
- auto bound = BrotliEncoderMaxCompressedSize(length);
+ const auto bound = BrotliEncoderMaxCompressedSize(length);
if (!bound) {
LOG(ERROR) << "BrotliEncoderMaxCompressedSize returned 0";
return {};
}
- auto buffer = std::make_unique<uint8_t[]>(bound);
+ std::basic_string<uint8_t> buffer(bound, '\0');
size_t encoded_size = bound;
auto rv = BrotliEncoderCompress(
BROTLI_DEFAULT_QUALITY, BROTLI_DEFAULT_WINDOW, BROTLI_DEFAULT_MODE, length,
- reinterpret_cast<const uint8_t*>(data), &encoded_size, buffer.get());
+ reinterpret_cast<const uint8_t*>(data), &encoded_size, buffer.data());
if (!rv) {
LOG(ERROR) << "BrotliEncoderCompress failed";
return {};
}
- return std::basic_string<uint8_t>(buffer.get(), encoded_size);
+ buffer.resize(encoded_size);
+ return buffer;
+ }
+ case kCowCompressLz4: {
+ const auto bound = LZ4_compressBound(length);
+ if (!bound) {
+ LOG(ERROR) << "LZ4_compressBound returned 0";
+ return {};
+ }
+ std::basic_string<uint8_t> buffer(bound, '\0');
+
+ const auto compressed_size = LZ4_compress_default(
+ static_cast<const char*>(data), reinterpret_cast<char*>(buffer.data()), length,
+ buffer.size());
+ if (compressed_size <= 0) {
+ LOG(ERROR) << "LZ4_compress_default failed, input size: " << length
+ << ", compression bound: " << bound << ", ret: " << compressed_size;
+ return {};
+ }
+ buffer.resize(compressed_size);
+ return buffer;
}
default:
LOG(ERROR) << "unhandled compression type: " << compression_;
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_format.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_format.h
index 9f4ddbb..ba75a8d 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_format.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_format.h
@@ -154,9 +154,12 @@
static constexpr uint8_t kCowSequenceOp = 7;
static constexpr uint8_t kCowFooterOp = -1;
-static constexpr uint8_t kCowCompressNone = 0;
-static constexpr uint8_t kCowCompressGz = 1;
-static constexpr uint8_t kCowCompressBrotli = 2;
+enum CowCompressionAlgorithm : uint8_t {
+ kCowCompressNone = 0,
+ kCowCompressGz = 1,
+ kCowCompressBrotli = 2,
+ kCowCompressLz4 = 3
+};
static constexpr uint8_t kCowReadAheadNotStarted = 0;
static constexpr uint8_t kCowReadAheadInProgress = 1;
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
index e17b5c6..e7a2f02 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/cow_writer.h
@@ -155,7 +155,7 @@
android::base::borrowed_fd fd_;
CowHeader header_{};
CowFooter footer_{};
- int compression_ = 0;
+ CowCompressionAlgorithm compression_ = kCowCompressNone;
uint64_t next_op_pos_ = 0;
uint64_t next_data_pos_ = 0;
uint32_t cluster_size_ = 0;
diff --git a/fs_mgr/libsnapshot/snapuserd/Android.bp b/fs_mgr/libsnapshot/snapuserd/Android.bp
index 57c599c..64e0b8a 100644
--- a/fs_mgr/libsnapshot/snapuserd/Android.bp
+++ b/fs_mgr/libsnapshot/snapuserd/Android.bp
@@ -87,6 +87,7 @@
"liblog",
"libsnapshot_cow",
"libz",
+ "liblz4",
"libext4_utils",
"liburing",
],
@@ -145,6 +146,7 @@
name: "cow_snapuserd_test",
defaults: [
"fs_mgr_defaults",
+ "libsnapshot_cow_defaults",
],
srcs: [
"dm-snapshot-merge/cow_snapuserd_test.cpp",
@@ -186,6 +188,7 @@
name: "snapuserd_test",
defaults: [
"fs_mgr_defaults",
+ "libsnapshot_cow_defaults",
],
srcs: [
"user-space-merge/snapuserd_test.cpp",
diff --git a/init/Android.bp b/init/Android.bp
index b4bc170..2dd9683 100644
--- a/init/Android.bp
+++ b/init/Android.bp
@@ -164,6 +164,7 @@
"libcgrouprc_format",
"libfsverity_init",
"liblmkd_utils",
+ "liblz4",
"libmini_keyctl_static",
"libmodprobe",
"libprocinfo",
@@ -362,6 +363,7 @@
"libext2_uuid",
"libprotobuf-cpp-lite",
"libsnapshot_cow",
+ "liblz4",
"libsnapshot_init",
"update_metadata-protos",
"libprocinfo",