* Misc minor performance improvements
* Use more concise loop syntax
* Use more concise Collection sort syntax
* Use StringUtils pad methods
* Optimize some loops and double-map-lookups
* Optimize array instantiation
There are two styles to convert a collection to an array: either
using a pre-sized array (like c.toArray(new String[c.size()])) or
using an empty array (like c.toArray(new String[0]).
In older Java versions using pre-sized array was recommended,
as the reflection call which is necessary to create an array
of proper size was quite slow. However since late updates of
OpenJDK 6 this call was intrinsified, making the performance
of the empty array version the same and sometimes even better,
compared to the pre-sized version. Also passing pre-sized array
is dangerous for a concurrent or synchronized collection as
a data race is possible between the size and toArray call
which may result in extra nulls at the end of the array,
if the collection was concurrently shrunk during the operation.
* Cleanup string concatenation
* Use EnumMap where possible
* Use FastMath instead of Math
* Initialize complex things only once
* Reduce method size to aloow more JIT inlining
* remove map of short->float
* Move field to local variable
* Cleanup Map lookup
Co-authored-by: Rob Ekl <xwq876@zebra.com>
Adds 500 ms delay to initial registering for samples from all tuners to
feed the spectral display/waterfall. The existing approach of immediately
registering for samples was causing the airspy tuner to lockup
aperiodically. Investigation via debugger didn't show any application
thread locks ... usb master processor was continuing to service libusb
timeouts. Unable to debug internal airspy processes. Adding the delay
to startup seems to be a usable solution.
produces a significant reduction in memory usage, especially for tuners
like the airspy and hackrf that produce 10/20 MSPS sample rates. This
is observed to be around 66% reduction in peak memory usage and provides
a more stable memory utilization across time reducing stress on the
garbage collector.
Use of these reusable memory buffers will be pushed further down into
the processing chain modules to ensure we keep new object creation
to the lowest levels possible.
