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Sean Owen commented on SPARK-21942: ----------------------------------- I suppose my real doubt is whether this would actually resolve the problem. mkdir -> mkdirs isn't a big deal of a change, but if an OS process is deleting files that Spark is still using, I don't know that there's any full 'fix' for that. I don't really object to the change, just don't think it really lets this situation work. > DiskBlockManager crashing when a root local folder has been externally > deleted by OS > ------------------------------------------------------------------------------------ > > Key: SPARK-21942 > URL: https://issues.apache.org/jira/browse/SPARK-21942 > Project: Spark > Issue Type: Bug > Components: Spark Core > Affects Versions: 1.6.1, 1.6.2, 1.6.3, 2.0.0, 2.0.1, 2.0.2, 2.1.0, 2.1.1, > 2.2.0, 2.2.1, 2.3.0, 3.0.0 > Reporter: Ruslan Shestopalyuk > Priority: Minor > Labels: storage > Fix For: 2.3.0 > > > _DiskBlockManager_ has a notion of a "scratch" local folder(s), which can be > configured via _spark.local.dir_ option, and which defaults to the system's > _/tmp_. The hierarchy is two-level, e.g. _/blockmgr-XXX.../YY_, where the > _YY_ part is a hash bit, to spread files evenly. > Function _DiskBlockManager.getFile_ expects the top level directories > (_blockmgr-XXX..._) to always exist (they get created once, when the spark > context is first created), otherwise it would fail with a message like: > {code} > ... java.io.IOException: Failed to create local dir in /tmp/blockmgr-XXX.../YY > {code} > However, this may not always be the case. > In particular, *if it's the default _/tmp_ folder*, there can be different > strategies of automatically removing files from it, depending on the OS: > * on the boot time > * on a regular basis (e.g. once per day via a system cron job) > * based on the file age > The symptom is that after the process (in our case, a service) using spark is > running for a while (a few days), it may not be able to load files anymore, > since the top-level scratch directories are not there and > _DiskBlockManager.getFile_ crashes. > Please note that this is different from people arbitrarily removing files > manually. > We have both the facts that _/tmp_ is the default in the spark config and > that the system has the right to tamper with its contents, and will do it > with a high probability, after some period of time. -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org