Fix Linux page size calculation (oshi#1060)

MR-Os1 · Dec 16, 2019 · 8ab50c0 · 8ab50c0
1 parent fd39349
commit 8ab50c0
Show file tree

Hide file tree

Showing 2 changed files with 4 additions and 16 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,6 +1,7 @@
 4.3.0 (in progress)
 ================
 * [#1057](https://github.com/oshi/oshi/pull/1057): Added Subnet Mask & Prefix Length to NetworkIF. - [@vesyrak](https://github.com/Vesyrak).
+* [#1060](https://github.com/oshi/oshi/pull/1057): Fixed Linux page size calculation. - [@dbwiddis](https://github.com/dbwiddis).
 
 4.2.0 (11/9/2019), 4.2.1 (11/14/2019)
 ================

diff --git a/oshi-core/src/main/java/oshi/hardware/platform/linux/LinuxGlobalMemory.java b/oshi-core/src/main/java/oshi/hardware/platform/linux/LinuxGlobalMemory.java
@@ -29,12 +29,6 @@
 import java.util.List;
 import java.util.function.Supplier;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import com.sun.jna.platform.linux.LibC; // NOSONAR squid:S1191
-import com.sun.jna.platform.linux.LibC.Sysinfo;
-
 import oshi.hardware.VirtualMemory;
 import oshi.hardware.common.AbstractGlobalMemory;
 import oshi.util.ExecutingCommand;
@@ -47,8 +41,6 @@
  */
 public class LinuxGlobalMemory extends AbstractGlobalMemory {
 
-    private static final Logger LOG = LoggerFactory.getLogger(LinuxGlobalMemory.class);
-
     private final Supplier<MemInfo> memInfo = memoize(this::readMemInfo, defaultExpiration());
 
     private final Supplier<Long> pageSize = memoize(this::queryPageSize);
@@ -76,14 +68,9 @@ public VirtualMemory getVirtualMemory() {
     }
 
     private long queryPageSize() {
-        try {
-            Sysinfo info = new Sysinfo();
-            if (0 == LibC.INSTANCE.sysinfo(info)) {
-                return info.mem_unit;
-            }
-        } catch (UnsatisfiedLinkError | NoClassDefFoundError e) {
-            LOG.debug("Failed to get sysinfo. {}", e);
-        }
+        // Ideally we would us sysconf(_SC_PAGESIZE) but the constant is platform
+        // dependent and would require parsing header files, etc. Since this is only
+        // read once at startup, command line is a reliable fallback.
         return ParseUtil.parseLongOrDefault(ExecutingCommand.getFirstAnswer("getconf PAGE_SIZE"), 4096L);
     }