Currently each CursorWindow allocates a 2MiB ashmem region to store
data, but this ends up being quite wasteful since the majority of
windows only end up storing a small handful of rows/columns. In
addition, creating and mmap'ing these ashmem regions requires
acquiring the mmap semaphore in the kernel, which can significantly
impact P95/P99 metrics when the system is under heavy load.
To mitigate the issues described above, this change adjusts
CursorWindow to send small windows (under 16KiB in size) directly
inline in Parcel responses without requiring an ashmem region.
CursorWindows also offer to gracefully "inflate" themselves into an
ashmem region when filled with more than 16KiB of data. This
requires some bugfixes around alloc() call sites to ensure that any
pointers are converted to offsets during a potential inflation.
The benchmarks referenced below show the following improvements
after this change is applied:
* Small cursor (1 row): 36% performance improvement
* Medium cursor (100 rows): no difference
* Large cursor (10k rows): no difference
Bug: 169251528
Test: atest CtsDatabaseTestCases
Test: atest FrameworksCoreTests:android.database
Test: ./frameworks/base/libs/hwui/tests/scripts/prep_generic.sh little && atest CorePerfTests:android.database.CrossProcessCursorPerfTest
Change-Id: Ie0fd149299f9847bf59a39f2855ed201bca4cdf6
Params of size_t use %zu formatting, while int64_t use PRId64. These
params had not been updated in a while since LOG_WINDOW is a no-op
macro when LOG_NDEBUG is off.
Test: Enable LOG_NDEBUG and do make
Change-Id: I59e9fa1aa343fd0a1da83c40fd24f3ef7bae5ed4
Replace calls to dup() with fcntl(F_DUPFD_CLOEXEC). The only difference
between the two is that O_CLOEXEC is set on the newly duped file
descriptor. This helps address file descriptor leaks crossing an exec()
boundary.
Test: compiles and boots
Bug: 120983106
Change-Id: Icc2ff2f7f398905aa8283c8797898114d34a9829
Check whether specified offset belongs to mData.
Also added a default argument bufferSize to check the end offset.
Size of the ashmem descriptor can be modified between
ashmem_get_size_region call and mmap. createFromParcel method was updated
to check ashmem size again immediately after memory is mapped.
Test: manual - using the test app from the bug
Bug: 34128677
Change-Id: I3ecd1616a870ce20941ce9b20a1843d2b4295750
Changes in this patch include
[x] Use %zu for size_t, %zd for ssize_t
[x] Some minor changes have been done to conform with
standard JNI practice (e.g. use of jint instead of int
in JNI function prototypes)
Change-Id: Id1aaa7894a7d0b85ac7ecd7b2bfd8cc40374261f
Signed-off-by: Ashok Bhat <ashok.bhat@arm.com>
Signed-off-by: Craig Barber <craig.barber@arm.com>
Signed-off-by: Kévin PETIT <kevin.petit@arm.com>
Signed-off-by: Marcus Oakland <marcus.oakland@arm.com>
No longer compile libandroidfw as a static library on the device
since it already exists as a shared library. Keeping the static
library would force us to provide a static library version of
libinput for the device as well which doesn't make sense.
Change-Id: I3517881b87b47dcc209d80dbd0ac6b5cf29a766f
