Recent (probably MacOS) mail app provoking endless cyrus.index writes on 2.3 server.

[Eric Luyten]

Howdy,


In recent weeks I have noticed a number of clients entering seemingly
endless loops writing the cyrus.index on a sometimes empty mailbox,
resulting in several dozen MB/s writing to our mail spool for hours on
end.

Always IMAP, never POP, sometimes TCP/143, mostly TCP/995

I enabled telemetry logging on several of these accounts and here's a
typical snippet :

<1444726821<1<1444726821<804.3507 IDLE
>1444726821>+ idling
<1444726821<D<1444726821<ONE
>1444726821>1804.3507 OK Completed
<1444726821<1<1444726821<805.3507 EXPUNGE
>1444726821>* 0 EXISTS
* 0 RECENT
1805.3507 OK Completed
<1444726821<1<1444726821<806.3507 IDLE
>1444726821>+ idling
<1444726821<D<1444726821<ONE
>1444726821>1806.3507 OK Completed
<1444726821<1<1444726821<807.3507 EXPUNGE
>1444726822>* 0 EXISTS
* 0 RECENT
1807.3507 OK Completed
<1444726822<1<1444726822<808.3507 IDLE
>1444726822>+ idling
<1444726822<D<1444726822<ONE
>1444726822>1808.3507 OK Completed
<1444726822<1<1444726822<809.3507 EXPUNGE
>1444726918>* 0 EXISTS
* 0 RECENT
1809.3507 OK Completed



Clues ?


Eric Luyten, Computing Centre VUB/ULB.