[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index]
[
List Home]
|
Re: [stellation-res] Timing: The Problem
|
On Fri, Sep 13, 2002 at 10:04:20AM -0400, Dave Shields wrote:
>
> I will post a followup note with the diff output showing my recent
> changes.
diff workspace/Checkin.java /home/shields/svc/org.eclipse.stellation.core/src/org/eclipse/stellation/workspace/Checkin.java
14a15
> import java.util.Date;
50a52,53
> long checkTime = new Long(new Date().getTime()).longValue();
> getWorkspace().setAttribute("checkout", new Long(checkTime).toString());
252a256
> getWorkspace().getFiles().waitCheck(checkTime);
diff workspace/Checkout.java /home/shields/svc/org.eclipse.stellation.core/src/org/eclipse/stellation/workspace/Checkout.java
57a58,59
> long checkTime = new Long(new Date().getTime()).longValue();
> getWorkspace().setAttribute("checkout", new Long(checkTime).toString());
139,140d140
< String checkoutTime = new Long(new Date().getTime()).toString();
< getWorkspace().setAttribute("checkout", checkoutTime);
213,224c213
< // Timer on file update time is only one second so need to
< // wait at least that long so that any new files created will
< // show different time
< try {
< synchronized (this) {
< wait(1050L);
< }
< }
< catch (InterruptedException e) {
< ; // Oh well, at least we tried to wait...
< }
<
---
> getWorkspace().getFiles().waitCheck(checkTime);
diff workspace/Configure.java /home/shields/svc/org.eclipse.stellation.core/src/org/eclipse/stellation/workspace/Configure.java
13a14
> import java.io.FileWriter;
15a17,18
> import java.util.Date;
>
53,60c56,64
< .add("database", "rest")
< .add("user", "rest")
< .add("password", "rest")
< .add("default")
< .add("empty")
< .add("option", "rest")
< .add("type", "rest")
< .add("within");
---
> .add("client")
> .add("database", "rest")
> .add("user", "rest")
> .add("password", "rest")
> .add("default")
> .add("empty")
> .add("option", "rest")
> .add("type", "rest")
> .add("within");
69c73,76
< if (name.equals("database")) {
---
> if (name.equals("client")) {
> client();
> }
> else if (name.equals("database")) {
105a113,174
> }
>
>
> class ConfigureClient {
> public long now() {
> return new Long(new Date().getTime()).longValue();
> }
> public long seconds(long time) {
> return time - ( time % 1000L);
> }
>
> public long elapsed(long now, long start) {
> return now - start;
> }
>
> public void configure () throws IOException {
> int passes = 25;
> long totalDifference = 0L;
> long start = seconds(now()); // Start time
> File file = File.createTempFile("svc-config","foo");
> for (int i = 0; i < passes; i++) {
> if (file.exists()) file.delete();
> FileWriter fileWriter = new FileWriter(file);
> fileWriter.write(new char[] {'b', 'a', 'r', '\n' });
> fileWriter.flush();
> fileWriter.close();
> long fileTime = file.lastModified();
> long now = now();
> if (fileTime > now) totalDifference += (fileTime - now);
> else if (fileTime < now) totalDifference += (now - fileTime);
> System.out.println("difference " + totalDifference);
> try {
> synchronized (this) {
> super.wait(100L);
> }
> }
> catch (InterruptedException e) {
> ; // Oh well, at least we tried to wait...
> }
> if (file.exists()) file.delete();
> }
> if (totalDifference == 0L) {
> System.out.println("No actoin needed.");
> return;
> }
>
> // Set configuration value at twice the average difference .
> long waitTime = (2L * totalDifference) / passes;
> Configuration configuration = getCurrentConfiguration();
> StringMap configurationOptions = configuration.getOptions();
> configurationOptions.put("svc-check-wait", new Long(waitTime).toString());
> outputConfiguration(configuration);
> }
>
> }
> /**
> * Configures client. Currently this involves determining if the obscure
> * svc-check-wait options should be used.
> */
> public void client() throws IOException {
> // Assume have write-access to current directory
> new ConfigureClient().configure();
diff workspace/Files.java /home/shields/svc/org.eclipse.stellation.core/src/org/eclipse/stellation/workspace/Files.java
95a96,97
> String checkWaitOption = _workspace.getContext().getOptions().get("svc-check-wait","");
> if (checkWaitOption.startsWith("-")) _trustClock = false;
1204a1207,1214
> * See if clock can be trusted.
> *
> */
> public boolean trustClock() {
> return _trustClock;
> }
>
> /**
1265a1276,1324
>
> /**
> * Waits until system clock has moved on to the next second after a
> * specified time.
> *
> * Even though times are measured in milliseconds, the resolution
> * of the times reported by File.lastModified() has been observed
> * to be at most one second. As a result, the command sequence:
> *<pre>
> * echo "old" > file
> * svc checkin
> * echo "new" > file
> * svc test modified
> *</pre>
> * may return spurious results if both svc commands are executed
> * in the same second, as the file time will appear to not have
> * changed. This method waits until the system clock has moved
> * into the 'next' second in order to avoid this problem.
> *
> *
> * @param checkTime the starting time for the wait. This time is
> * noted by the checkout and checkin commands as they start
> * execution, as no workspace file can have a modification time
> * later than this time
> */
> public void waitCheck(long checkTime) {
> String checkWaitOption = getWorkspace().getContext().getOptions().get("svc-check-wait","");
> if (checkWaitOption.equals("")
> || checkWaitOption.equals("0")
> || checkWaitOption.startsWith("-"))
> return;
> checkTime = checkTime - (checkTime% 1000L); // round down to nearest second
> long waitTime = new Long(checkWaitOption).longValue();
> //
> long currentTime = new Long(new Date().getTime()).longValue();
> while (currentTime > checkTime && currentTime < (checkTime + waitTime)) {
> System.out.println("check-wait waiting");
> try {
> synchronized (this) {
> wait(100L); // Wait 100 milliseconds.
> }
> }
> catch (InterruptedException e) {
> ;
> }
> currentTime = new Long(new Date().getTime()).longValue();
> }
> }
>
1282a1342,1343
>
> protected boolean _trustClock = true; // Assume system clock and file modification time accurate
diff workspace/Project.java /home/shields/svc/org.eclipse.stellation.core/src/org/eclipse/stellation/workspace/Project.java
643a644
> boolean trustClock = _workspace.getFiles().trustClock();
664,667c665,675
< long entryTime = new Long(eAttributes.get("time")).longValue();
< long lastModified = file.lastModified();
< if (entryTime != lastModified) {
< artifact.setTime(lastModified);
---
> if (trustClock) {
> long entryTime = new Long(eAttributes.get("time")).longValue();
> long lastModified = file.lastModified();
> if (entryTime != lastModified) {
> artifact.setTime(lastModified);
> artifact.computeSignature();
> }
> }
> else {
> // No need to set modification time if not trusting clock,
> // but must compute signature
diff workspace/Svc.java /home/shields/svc/org.eclipse.stellation.core/src/org/eclipse/stellation/workspace/Svc.java
390a391
> .add("svc-check-wait", "property", true)
--
Dave Shields, IBM Research, shields@xxxxxxxxxxxxxx.
