On Mon, 9 Sep 2024 11:42:25 GMT, Aleksei Efimov <aefi...@openjdk.org> wrote:
>> This PR proposes the following changes to address wrong timeout computations >> in the `com.sun.jndi.dns.DnsClient`: >> - The `DnsClient` has been updated to use a monotonic high-resolution (nano) >> clock. The existing `Timeout` test has also been updated to use the nano >> clock to measure observed timeout value. >> >> - The left timeout computation has been fixed to decrease the timeout value >> during each retry attempt. A new test, `TimeoutWithEmptyDatagrams`, has been >> added to test it. >> >> - The `DnsClient.blockingReceive` has been updated: >> - to detect if any data is received >> - to avoid contention with `Selector.close()` that could be called by a >> cleaner thread >> >> - The expected timeout calculation in the `Timeout` test has been updated to >> take into account the minimum retry timeout (50ms). Additionally, the max >> allowed difference between the observed timeout and the expected one has >> been increased from 50% to 67%. Taking into account 50 ms retry timeout >> decrease the maximum allowed difference is effectively set to 61%. This >> change is expected to improve the stability of the `Timeout` test which has >> been seen to fail >> [intermittentlly](https://bugs.openjdk.org/browse/JDK-8220213). If no >> objections, I'm planning to close >> [JDK-8220213](https://bugs.openjdk.org/browse/JDK-8220213) as duplicate of >> this one. >> >> JNDI/DNS jtreg tests has been executed multiple times (500+) to check if the >> new and the modified tests are stable. No failures been observed (so far?). > > Aleksei Efimov has updated the pull request incrementally with two additional > commits since the last revision: > > - guard against possible integer value overflows > - make startTime a local variable src/jdk.naming.dns/share/classes/com/sun/jndi/dns/DnsClient.java line 440: > 438: InetSocketAddress target = new InetSocketAddress(server, > port); > 439: udpChannel.connect(target); > 440: long pktTimeout = (timeout * (1L << retry)); Suggestion: // use 1L below to ensure conversion to long and avoid potential // integer overflow (timeout is an int) long pktTimeout = (timeout * (1L << retry)); src/jdk.naming.dns/share/classes/com/sun/jndi/dns/DnsClient.java line 444: > 442: > 443: // timeout remaining after successive 'blockingReceive()' > 444: long timeoutLeft = Math.clamp(pktTimeout, 0, > Integer.MAX_VALUE); Suggestion: // no point in supporting timeout > Integer.MAX_VALUE, clamp if needed long timeoutLeft = Math.clamp(pktTimeout, 0, Integer.MAX_VALUE); ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/20892#discussion_r1750444825 PR Review Comment: https://git.openjdk.org/jdk/pull/20892#discussion_r1750447201
