core: add MemoryAvailable unit property

Try to infer the unused memory that a unit can claim before the
memory.max limit is reached, including any limit set on any parent
slice above the unit itself.

1 files changed, 29 insertions, 0 deletions

diff --git a/man/org.freedesktop.systemd1.xml b/man/org.freedesktop.systemd1.xml
index d55f3c8f9b..1edaf157b9 100644
--- a/man/org.freedesktop.systemd1.xml
+++ b/man/org.freedesktop.systemd1.xml
@@ -2401,6 +2401,8 @@ node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice {
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t MemoryCurrent = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+      readonly t MemoryAvailable = ...;
+      @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t CPUUsageNSec = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly ay EffectiveCPUs = [...];
@@ -3504,6 +3506,8 @@ node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice {
 
     <variablelist class="dbus-property" generated="True" extra-ref="MemoryCurrent"/>
 
+    <variablelist class="dbus-property" generated="True" extra-ref="MemoryAvailable"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="CPUUsageNSec"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="EffectiveCPUs"/>
@@ -4063,6 +4067,11 @@ node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2eservice {
       <varname>MountImages</varname>
       <varname>ExtensionImages</varname>
       see systemd.exec(5) for their meaning.</para>
+
+      <para><varname>MemoryAvailable</varname> indicates how much unused memory is available to the unit before
+      the <literal>MemoryMax</literal> or <literal>MemoryHigh</literal> (whichever is lower) limit set by the cgroup
+      memory controller is reached. It will take into consideration limits on all parent slices, other than the
+      limits set on the unit itself.</para>
     </refsect2>
   </refsect1>
 
@@ -4196,6 +4205,8 @@ node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2esocket {
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t MemoryCurrent = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+      readonly t MemoryAvailable = ...;
+      @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t CPUUsageNSec = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly ay EffectiveCPUs = [...];
@@ -5321,6 +5332,8 @@ node /org/freedesktop/systemd1/unit/avahi_2ddaemon_2esocket {
 
     <variablelist class="dbus-property" generated="True" extra-ref="MemoryCurrent"/>
 
+    <variablelist class="dbus-property" generated="True" extra-ref="MemoryAvailable"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="CPUUsageNSec"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="EffectiveCPUs"/>
@@ -5915,6 +5928,8 @@ node /org/freedesktop/systemd1/unit/home_2emount {
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t MemoryCurrent = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+      readonly t MemoryAvailable = ...;
+      @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t CPUUsageNSec = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly ay EffectiveCPUs = [...];
@@ -6886,6 +6901,8 @@ node /org/freedesktop/systemd1/unit/home_2emount {
 
     <variablelist class="dbus-property" generated="True" extra-ref="MemoryCurrent"/>
 
+    <variablelist class="dbus-property" generated="True" extra-ref="MemoryAvailable"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="CPUUsageNSec"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="EffectiveCPUs"/>
@@ -7601,6 +7618,8 @@ node /org/freedesktop/systemd1/unit/dev_2dsda3_2eswap {
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t MemoryCurrent = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+      readonly t MemoryAvailable = ...;
+      @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t CPUUsageNSec = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly ay EffectiveCPUs = [...];
@@ -8544,6 +8563,8 @@ node /org/freedesktop/systemd1/unit/dev_2dsda3_2eswap {
 
     <variablelist class="dbus-property" generated="True" extra-ref="MemoryCurrent"/>
 
+    <variablelist class="dbus-property" generated="True" extra-ref="MemoryAvailable"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="CPUUsageNSec"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="EffectiveCPUs"/>
@@ -9112,6 +9133,8 @@ node /org/freedesktop/systemd1/unit/system_2eslice {
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t MemoryCurrent = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+      readonly t MemoryAvailable = ...;
+      @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t CPUUsageNSec = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly ay EffectiveCPUs = [...];
@@ -9403,6 +9426,8 @@ node /org/freedesktop/systemd1/unit/system_2eslice {
 
     <variablelist class="dbus-property" generated="True" extra-ref="MemoryCurrent"/>
 
+    <variablelist class="dbus-property" generated="True" extra-ref="MemoryAvailable"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="CPUUsageNSec"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="EffectiveCPUs"/>
@@ -9571,6 +9596,8 @@ node /org/freedesktop/systemd1/unit/session_2d1_2escope {
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t MemoryCurrent = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+      readonly t MemoryAvailable = ...;
+      @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly t CPUUsageNSec = ...;
       @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
       readonly ay EffectiveCPUs = [...];
@@ -9904,6 +9931,8 @@ node /org/freedesktop/systemd1/unit/session_2d1_2escope {
 
     <variablelist class="dbus-property" generated="True" extra-ref="MemoryCurrent"/>
 
+    <variablelist class="dbus-property" generated="True" extra-ref="MemoryAvailable"/>
+
     <variablelist class="dbus-property" generated="True" extra-ref="CPUUsageNSec"/>
 
     <variablelist class="dbus-property" generated="True" extra-ref="EffectiveCPUs"/>