On Sat, Nov 26, 2011 at 5:10 PM, lars hofhansl <[email protected]> wrote: > Are you sure this works? > > According to this: > http://bugs.sun.com/view_bug.do;jsessionid=ff625daf459fdffffffffcd54f1c775299e0?bug_id=6202721 > the JDK will treat /dev/urandom as a special string and use /dev/random > anyway (hence the workaround with /dev/./urandom)
It worked for me so long as I had enough slashes - file:///dev/urandom and not file:/dev/urandom as some other resources showed. -Todd > > > ----- Original Message ----- > From: Todd Lipcon <[email protected]> > To: [email protected] > Cc: lars hofhansl <[email protected]> > Sent: Friday, November 25, 2011 10:22 PM > Subject: Re: Status of 0.92RC > > In Hadoop we use this in our pom: > <java.security.egd>file:///dev/urandom</java.security.egd> > > which also works in JDK6. See HADOOP-7841 > > > On Fri, Nov 25, 2011 at 10:12 PM, Li Pi <[email protected]> wrote: >> Very, very nice discovery! >> >> Once I saw the move your mouse around part, I smiled. >> >> Entropy can also be gathered from other system events, such as network >> traffic, so on a production machine, you should always have enough >> entropy. So it should be fine to change the test to use urandom. >> >> On Fri, Nov 25, 2011 at 9:06 PM, lars hofhansl <[email protected]> wrote: >>> Here is something that will boggle your mind: >>> After you ran TestHCM often enough it will hang until you move your mouse >>> around! >>> >>> No joke... But what sounds like an impossibility is actually related to the >>> use of SecureRandom. >>> SecureRandom uses /dev/random on Linux and that gathers entropy from system >>> events >>> such as network activity, disk activity, keyboard activity, mouse movement, >>> etc. >>> If not enough the entropy is available /dev/random will block until enough >>> entropy is gathered! >>> >>> When I add this to the command line (via pom.xml) TestHCM never hangs: >>> "-Djava.security.egd=file:/dev/./urandom" >>> >>> (note that -Djava.security.egd=file:/dev/urandom does not work for some >>> reason on JDK 1.5 or newer, the extra ./ is needed) >>> >>> >>> This instructs the JDK use /dev/urandom for SecureRandom, which unlike >>> /dev/random will never block, but if not enough >>> entropy exists it will generate random numbers of lesser quality... But for >>> tests we don't care. >>> >>> >>> That explains why tests only time out sometimes... when the system happens >>> to run out of entropy bits when a secure random >>> is used. >>> >>> -- Lars >>> >>> >>> ________________________________ >>> From: Stack <[email protected]> >>> To: [email protected] >>> Cc: lars hofhansl <[email protected]> >>> Sent: Friday, November 25, 2011 7:14 PM >>> Subject: Re: Status of 0.92RC >>> >>> On Fri, Nov 25, 2011 at 6:16 PM, Ted Yu <[email protected]> wrote: >>>> I then looped TestHCM 4 times and there was no test failure. >>>> >>> >>> Its fine on mac. On ubuntu: >>> >>> ------------------------------------------------------------------------------- >>> Test set: org.apache.hadoop.hbase.client.TestHCM >>> ------------------------------------------------------------------------------- >>> Tests run: 5, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: >>> 757.578 sec <<< FAILURE! >>> testClosing(org.apache.hadoop.hbase.client.TestHCM) Time elapsed: >>> 35.34 sec <<< FAILURE! >>> java.lang.AssertionError >>> at org.junit.Assert.fail(Assert.java:92) >>> at org.junit.Assert.assertTrue(Assert.java:43) >>> at org.junit.Assert.assertFalse(Assert.java:68) >>> at org.junit.Assert.assertFalse(Assert.java:79) >>> at >>> org.apache.hadoop.hbase.client.TestHCM.testClosing(TestHCM.java:221) >>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) >>> >>> .... >>> >>> Line numbers are off because I'm messing. Its saying connection 1 is >>> closed if I test it just after creating it. >>> >>> St.Ack >>> >>>> On Fri, Nov 25, 2011 at 5:39 PM, Ted Yu <[email protected]> wrote: >>>> >>>>> I looped TestHCM#testClosing 5 times on MacBook and didn't see test >>>>> failure. >>>>> >>>>> Stack: >>>>> Can you share the test output ? >>>>> >>>>> Thanks >>>>> >>>>> >>>>> On Fri, Nov 25, 2011 at 5:04 PM, lars hofhansl <[email protected]>wrote: >>>>> >>>>>> I added testClosing as part of HBASE-4805, I'll have a look as soon as I >>>>>> get a chance. >>>>>> >>>>>> >>>>>> >>>>>> ________________________________ >>>>>> From: Stack <[email protected]> >>>>>> To: HBase Dev List <[email protected]> >>>>>> Sent: Friday, November 25, 2011 2:12 PM >>>>>> Subject: Status of 0.92RC >>>>>> >>>>>> I'm having a little difficulty getting all tests to pass. On >>>>>> linux/ubuntu, TestHCM (testClosing strange issue) and TestReplication >>>>>> are failing for me. On mac osx, it'll build without fail about 50% of >>>>>> the time. I'd like to make it so tests pass all the time before >>>>>> cutting the RC. Thats what I'm at these times. >>>>>> >>>>>> Also, 0.92 build on jenkins has been turned off by Apache >>>>>> Infrastructure. It was hanging. Its done this in the past too and >>>>>> when it hangs it requires a jenkins reboot which doesn't make Apache >>>>>> Infrastructure team too happy. The hang looks to me like a Jenkins >>>>>> bug because build hangs before we even checkout src. Am trying to see >>>>>> what can be done to get it going again but thats the story at the mo. >>>>>> >>>>>> St.Ack >>>>>> >>>>> >>>>> >>>> >>> >> > > > > -- > Todd Lipcon > Software Engineer, Cloudera > > -- Todd Lipcon Software Engineer, Cloudera
