Merge branch 'hjespersen/set-nperiods'

README.md

@@ -26,6 +26,7 @@ server = jack_server.Server(
     device="BuiltInSpeakerDevice",
     rate=48000,
     period=1024,
+    # nperiods=2  # Work only with `alsa` driver
 )
 server.start()
 
@@ -93,6 +94,12 @@ Sampling rate.
 
 Buffer size.
 
+#### `nperiods: int`
+
+Number of periods. 2 is right for motherboard, PCI, PCI-X, etc.; 3 for USB ([source](https://wiki.archlinux.org/title/JACK_Audio_Connection_Kit)).
+
+Can be helpful when tailoring performance on jittery systems.
+
 #### `params: dict[str, jack_server.Parameter]`
 
 Driver parameters mapped by name.

src/jack_server/_driver.py

@@ -49,5 +49,15 @@ def period(self) -> int:
     def period(self, __value: int) -> None:
         self.params["period"].value = __value
 
+    @property
+    def nperiods(self) -> int:  # pragma: no cover (works only with alsa driver)
+        return cast(int, self.params["nperiods"].value)
+
+    @nperiods.setter
+    def nperiods(
+        self, __value: int
+    ) -> None:  # pragma: no cover (works only with alsa driver)
+        self.params["nperiods"].value = __value
+
     def __repr__(self) -> str:
         return f"<jack_server.Driver name={self.name}>"

src/jack_server/_server.py

@@ -51,6 +51,7 @@ def __init__(
         device: str | SetByJack = SetByJack_,
         rate: SampleRate | SetByJack = SetByJack_,
         period: int | SetByJack = SetByJack_,
+        nperiods: int | SetByJack = SetByJack_,
     ) -> None:
         self._created = False
         self._opened = False
@@ -68,11 +69,17 @@ def __init__(
         if not isinstance(realtime, SetByJack):
             self.realtime = realtime
         if not isinstance(device, SetByJack):
-            self.driver.device = device  # pragma: no cover (can't set driver on dummy driver that used in CI)
+            self.driver.device = (
+                device  # pragma: no cover (does not work with dummy driver)
+            )
         if not isinstance(rate, SetByJack):
             self.driver.rate = rate
         if not isinstance(period, SetByJack):
             self.driver.period = period
+        if not isinstance(
+            nperiods, SetByJack
+        ):  # pragma: no cover (works only with alsa driver)
+            self.driver.nperiods = nperiods
 
     def _create(
         self,