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https://issues.apache.org/jira/browse/HDFS-14317?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16781318#comment-16781318
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Ekanth Sethuramalingam commented on HDFS-14317:
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{quote}That's not true, they both accept time units. You can do something like
"10ms" and it will parse it properly. This is only in Hadoop 3+
{quote}
Thanks [~xkrogen] for pointing this out. However, as I looked deeper in the
code, the value is converted to seconds which will lose the precision.
{code:java}
logRollPeriodMs = conf.getTimeDuration(
DFSConfigKeys.DFS_HA_LOGROLL_PERIOD_KEY,
DFSConfigKeys.DFS_HA_LOGROLL_PERIOD_DEFAULT, TimeUnit.SECONDS) * 1000;
{code}
and
{code:java}
sleepTimeMs = conf.getTimeDuration(
DFSConfigKeys.DFS_HA_TAILEDITS_PERIOD_KEY,
DFSConfigKeys.DFS_HA_TAILEDITS_PERIOD_DEFAULT, TimeUnit.SECONDS) * 1000;
{code}
I guess I'll leave it as it is. I'll upload a new patch in a bit.
> Standby does not trigger edit log rolling when in-progress edit log tailing
> is enabled
> --------------------------------------------------------------------------------------
>
> Key: HDFS-14317
> URL: https://issues.apache.org/jira/browse/HDFS-14317
> Project: Hadoop HDFS
> Issue Type: Bug
> Affects Versions: 2.9.0, 3.0.0
> Reporter: Ekanth Sethuramalingam
> Assignee: Ekanth Sethuramalingam
> Priority: Critical
> Attachments: HDFS-14317.001.patch
>
>
> The standby uses the following method to check if it is time to trigger edit
> log rolling on active.
> {code}
> /**
> * @return true if the configured log roll period has elapsed.
> */
> private boolean tooLongSinceLastLoad() {
> return logRollPeriodMs >= 0 &&
> (monotonicNow() - lastLoadTimeMs) > logRollPeriodMs ;
> }
> {code}
> In doTailEdits(), lastLoadTimeMs is updated when standby is able to
> successfully tail any edits
> {code}
> if (editsLoaded > 0) {
> lastLoadTimeMs = monotonicNow();
> }
> {code}
> The default configuration for {{dfs.ha.log-roll.period}} is 120 seconds and
> {{dfs.ha.tail-edits.period}} is 60 seconds. With in-progress edit log tailing
> enabled, tooLongSinceLastLoad() will almost never return true resulting in
> edit logs not rolled for a long time until this configuration
> {{dfs.namenode.edit.log.autoroll.multiplier.threshold}} takes effect.
> [In our deployment, this resulted in in-progress edit logs getting deleted.
> The sequence of events is that standby was able to checkpoint twice while the
> in-progress edit log was growing on active. When the
> NNStorageRetentionManager decided to cleanup old checkpoints and edit logs,
> it cleaned up the in-progress edit log from active and QJM (as the txnid on
> in-progress edit log was older than the 2 most recent checkpoints) resulting
> in irrecoverably losing a few minutes worth of metadata].
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