Bug 550291

Description Xavier Raynaud 2019-08-21 04:44:08 EDT

I'm using Eclipse 2019-06, with jgit 5.4.0.201906121030-r

I'm on Linux (centos7), and my HOME dir is on NFS (I think it's important).

To reproduce the issue, just click on "Window->Preferences->Team->Git->Configuration"

While debugging the issue, I discover that the thread "main" loop forever in the following code:
(in org.eclipse.jgit.util.FS.java:231)


		private FileStoreAttributeCache(Path dir)
				throws IOException, InterruptedException {
			Path probe = dir.resolve(".probe-" + UUID.randomUUID()); //$NON-NLS-1$
			Files.createFile(probe);
			try {
				FileTime startTime = Files.getLastModifiedTime(probe);
				FileTime actTime = startTime;
				long sleepTime = 512;
				while (actTime.compareTo(startTime) <= 0) {
					TimeUnit.NANOSECONDS.sleep(sleepTime);
					FileUtils.touch(probe);
					actTime = Files.getLastModifiedTime(probe);
					// limit sleep time to max. 100ms
					if (sleepTime < 100_000_000L) {
						sleepTime = sleepTime * 2;
					}
				}
				fsTimestampResolution = Duration.between(startTime.toInstant(),
						actTime.toInstant());
			} catch (AccessDeniedException e) {
				LOG.error(e.getLocalizedMessage(), e);
			} finally {
				Files.delete(probe);
			}
		}


The comparison in the while loop returns always zero, leading to infinite loop.
See also https://lwn.net/Articles/564120/ about NFS and timestamps

See also https://bugs.eclipse.org/bugs/show_bug.cgi?id=548188



It's probably similar to