Error in data flush background thread

Recently Nexus was upgraded from 2.14.5 to 3.25.0.
After this upgrade we experience intermiddent issues where we are unable to upload/download artifacts from the repositories. This presents itself as a generic error 500

The logs indicate a file cannot be found/read such as

nexus3\db\component\asset.pcl
or
nexus3\db\component\asset_name_ci_idx.sbt

Restarting the Nexus service fixes the problem, though only temporarily.
Any help towards a more permanent fix is greatly appreciated.

The full log contains the following

2020-11-19 19:31:14,938+0100 ERROR [qtp1578666736-8898]  *UNKNOWN com.orientechnologies.orient.core.storage.impl.local.paginated.OLocalPaginatedStorage - Exception `7B9F486D` in storage `plocal:E:/nexus/sonatype-work/nexus3/db/component`: 2.2.36 (build d3beb772c02098ceaea89779a7afd4b7305d3788, branch 2.2.x)
com.orientechnologies.orient.core.exception.OStorageException: Error in data flush background thread, please restart database and send full stack trace inside of bug report
	DB name="component"
	at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.checkLowDiskSpaceRequestsAndReadOnlyConditions(OAbstractPaginatedStorage.java:5104)
	at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.commit(OAbstractPaginatedStorage.java:1729)
	at com.orientechnologies.orient.core.tx.OTransactionOptimistic.doCommit(OTransactionOptimistic.java:541)
	at com.orientechnologies.orient.core.tx.OTransactionOptimistic.commit(OTransactionOptimistic.java:99)
	at com.orientechnologies.orient.core.db.document.ODatabaseDocumentTx.commit(ODatabaseDocumentTx.java:2908)
	at com.orientechnologies.orient.core.db.document.ODatabaseDocumentTx.commit(ODatabaseDocumentTx.java:2870)
	at org.sonatype.nexus.repository.storage.StorageTxImpl.commit(StorageTxImpl.java:182)
	at sun.reflect.GeneratedMethodAccessor81.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.sonatype.nexus.common.stateguard.SimpleMethodInvocation.proceed(SimpleMethodInvocation.java:53)
	at org.sonatype.nexus.common.stateguard.MethodInvocationAction.run(MethodInvocationAction.java:39)
	at org.sonatype.nexus.common.stateguard.StateGuard$TransitionImpl.run(StateGuard.java:193)
	at org.sonatype.nexus.common.stateguard.TransitionsInterceptor.invoke(TransitionsInterceptor.java:56)
	at org.sonatype.nexus.common.stateguard.StateGuardAspect$1.invoke(StateGuardAspect.java:66)
	at com.sun.proxy.$Proxy213.commit(Unknown Source)
	at org.sonatype.nexus.transaction.TransactionalWrapper.proceedWithTransaction(TransactionalWrapper.java:68)
	at org.sonatype.nexus.transaction.TransactionInterceptor.proceedWithTransaction(TransactionInterceptor.java:66)
	at org.sonatype.nexus.transaction.TransactionInterceptor.invoke(TransactionInterceptor.java:55)
	at com.google.inject.internal.InterceptorStackCallback$InterceptedMethodInvocation.proceed(InterceptorStackCallback.java:78)
	at com.google.inject.internal.InterceptorStackCallback.intercept(InterceptorStackCallback.java:54)
	at org.sonatype.nexus.repository.storage.LastDownloadedHandler$$EnhancerByGuice$$baa422f.tryPersistLastDownloadedTime(<generated>)
	at org.sonatype.nexus.repository.storage.LastDownloadedHandler.maybeUpdateLastDownloaded(LastDownloadedHandler.java:83)
	at org.sonatype.nexus.repository.storage.LastDownloadedHandler.maybeUpdateLastDownloaded(LastDownloadedHandler.java:75)
	at org.sonatype.nexus.repository.storage.LastDownloadedHandler.handle(LastDownloadedHandler.java:64)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.storage.UnitOfWorkHandler.handle(UnitOfWorkHandler.java:39)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.ContentHeadersHandler.handle(ContentHeadersHandler.java:46)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.maven.internal.orient.OrientVersionPolicyHandler.handle(OrientVersionPolicyHandler.java:56)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.http.PartialFetchHandler.handle(PartialFetchHandler.java:59)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.cache.NegativeCacheHandler.handle(NegativeCacheHandler.java:56)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.ConditionalRequestHandler.handle(ConditionalRequestHandler.java:72)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at com.sonatype.nexus.clm.internal.FirewallContributedHandler.handle(FirewallContributedHandler.java:98)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.HandlerContributor.handle(HandlerContributor.java:67)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.ExceptionHandler.handle(ExceptionHandler.java:42)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.routing.internal.RoutingRuleHandler.handle(RoutingRuleHandler.java:52)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.security.SecurityHandler.handle(SecurityHandler.java:51)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.TimingHandler.handle(TimingHandler.java:58)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.Context.start(Context.java:114)
	at org.sonatype.nexus.repository.view.Router.dispatch(Router.java:65)
	at org.sonatype.nexus.repository.view.ConfigurableViewFacet.dispatch(ConfigurableViewFacet.java:52)
	at org.sonatype.nexus.repository.group.GroupHandler.getFirst(GroupHandler.java:134)
	at org.sonatype.nexus.repository.group.GroupHandler.doGet(GroupHandler.java:111)
	at org.sonatype.nexus.repository.group.GroupHandler.handle(GroupHandler.java:95)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.http.PartialFetchHandler.handle(PartialFetchHandler.java:59)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.ConditionalRequestHandler.handle(ConditionalRequestHandler.java:72)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at com.sonatype.nexus.clm.internal.FirewallContributedHandler.handle(FirewallContributedHandler.java:98)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.HandlerContributor.handle(HandlerContributor.java:67)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.ExceptionHandler.handle(ExceptionHandler.java:42)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.routing.internal.RoutingRuleHandler.handle(RoutingRuleHandler.java:52)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.security.SecurityHandler.handle(SecurityHandler.java:51)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.handlers.TimingHandler.handle(TimingHandler.java:58)
	at org.sonatype.nexus.repository.view.Context.proceed(Context.java:80)
	at org.sonatype.nexus.repository.view.Context.start(Context.java:114)
	at org.sonatype.nexus.repository.view.Router.dispatch(Router.java:65)
	at org.sonatype.nexus.repository.view.ConfigurableViewFacet.dispatch(ConfigurableViewFacet.java:52)
	at org.sonatype.nexus.repository.view.ConfigurableViewFacet.dispatch(ConfigurableViewFacet.java:43)
	at org.sonatype.nexus.repository.httpbridge.internal.ViewServlet.dispatchAndSend(ViewServlet.java:212)
	at org.sonatype.nexus.repository.httpbridge.internal.ViewServlet.doService(ViewServlet.java:174)
	at org.sonatype.nexus.repository.httpbridge.internal.ViewServlet.service(ViewServlet.java:126)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at com.google.inject.servlet.ServletDefinition.doServiceImpl(ServletDefinition.java:290)
	at com.google.inject.servlet.ServletDefinition.doService(ServletDefinition.java:280)
	at com.google.inject.servlet.ServletDefinition.service(ServletDefinition.java:184)
	at com.google.inject.servlet.DynamicServletPipeline.service(DynamicServletPipeline.java:71)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:85)
	at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:112)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61)
	at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
	at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
	at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
	at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
	at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
	at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
	at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
	at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
	at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
	at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
	at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
	at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
	at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108)
	at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137)
	at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
	at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66)
	at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449)
	at org.sonatype.nexus.security.SecurityFilter.executeChain(SecurityFilter.java:85)
	at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365)
	at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90)
	at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83)
	at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:387)
	at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362)
	at org.sonatype.nexus.security.SecurityFilter.doFilterInternal(SecurityFilter.java:101)
	at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at org.sonatype.nexus.repository.httpbridge.internal.ExhaustRequestFilter.doFilter(ExhaustRequestFilter.java:80)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at com.sonatype.nexus.licensing.internal.LicensingRedirectFilter.doFilter(LicensingRedirectFilter.java:116)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at com.codahale.metrics.servlet.AbstractInstrumentedFilter.doFilter(AbstractInstrumentedFilter.java:112)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at org.sonatype.nexus.internal.web.ErrorPageFilter.doFilter(ErrorPageFilter.java:79)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at org.sonatype.nexus.internal.web.EnvironmentFilter.doFilter(EnvironmentFilter.java:101)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at org.sonatype.nexus.internal.web.HeaderPatternFilter.doFilter(HeaderPatternFilter.java:98)
	at com.google.inject.servlet.FilterChainInvocation.doFilter(FilterChainInvocation.java:82)
	at com.google.inject.servlet.DynamicFilterPipeline.dispatch(DynamicFilterPipeline.java:104)
	at com.google.inject.servlet.GuiceFilter.doFilter(GuiceFilter.java:133)
	at org.sonatype.nexus.bootstrap.osgi.DelegatingFilter.doFilter(DelegatingFilter.java:73)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1602)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:540)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146)
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257)
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1700)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1345)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:480)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1667)
	at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1247)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
	at com.codahale.metrics.jetty9.InstrumentedHandler.handle(InstrumentedHandler.java:239)
	at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:152)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
	at org.eclipse.jetty.server.Server.handle(Server.java:505)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:370)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:267)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
	at org.eclipse.jetty.io.ssl.SslConnection$DecryptedEndPoint.onFillable(SslConnection.java:427)
	at org.eclipse.jetty.io.ssl.SslConnection.onFillable(SslConnection.java:321)
	at org.eclipse.jetty.io.ssl.SslConnection$2.succeeded(SslConnection.java:159)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
	at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:117)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)
	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:698)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:804)
	at java.lang.Thread.run(Thread.java:748)
Caused by: com.orientechnologies.common.io.OIOException: Error during file open
	at com.orientechnologies.orient.core.storage.fs.OFileClassic.open(OFileClassic.java:590)
	at com.orientechnologies.common.collection.closabledictionary.OClosableEntry.makeAcquiredFromClosed(OClosableEntry.java:102)
	at com.orientechnologies.common.collection.closabledictionary.OClosableLinkedContainer.acquire(OClosableLinkedContainer.java:297)
	at com.orientechnologies.orient.core.storage.cache.local.OWOWCache$PeriodicalFuzzyCheckpointTask.run(OWOWCache.java:2196)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
	at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	... 1 common frames omitted
Caused by: java.io.FileNotFoundException: E:\nexus\sonatype-work\nexus3\db\component\asset_name_ci_idx.sbt (The process cannot access the file because it is being used by another process)
	at java.io.RandomAccessFile.open0(Native Method)
	at java.io.RandomAccessFile.open(RandomAccessFile.java:316)
	at java.io.RandomAccessFile.<init>(RandomAccessFile.java:243)
	at com.orientechnologies.orient.core.storage.fs.OFileClassic.openChannel(OFileClassic.java:675)
	at com.orientechnologies.orient.core.storage.fs.OFileClassic.open(OFileClassic.java:580)
	... 10 common frames omitted

Caused by: java.io.FileNotFoundException: E:\nexus\sonatype-work\nexus3\db\component\asset_name_ci_idx.sbt (The process cannot access the file because it is being used by another process)

Some other process is holding file locks against database files. Is there a virus scanner on this system? If so, you should exclude the work directory from scanning.