[Dovecot] imap processes eating IO

Sun Jul 27 20:09:41 EEST 2008

[Ignore the previous e-mail, I somehow sent it when I was trying to 
paste from clipboard]

I recently migrated my dovecot/postfix setup to a new machine.  After 
doing so, I have encountered a problem where imap processes get stuck in 
a loop eating loads of IO on the machine.  Looking at the trace (snippet 
below), it looks like they are sitting and reading the inbox and other 
folders of certain users repeatedly.  This seems to be triggered by the 
delivery of a new e-mail to the user's mailbox while they have an IMAP 
client connected, though I cannot say for sure.

This had never happened before on the old machine.  I'm certain more 
information would be useful, please let me know what I can provide to help!

Trace of process 22342 - imap
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203440140.P6242Q0M41485.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=3079, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203446630.P7458Q0M562949.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=27769, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203454830.P9042Q0M402016.scarecrow:2,RSe", 
{st_mode=S_IFREG|0600, st_size=730534, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203460967.P10096Q0M631472.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=2690, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203463833.P10601Q0M946162.scarecrow:2,Sbc", 
{st_mode=S_IFREG|0600, st_size=2319, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203468449.P11425Q0M422185.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2650, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203469387.P11575Q0M276926.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1317, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203472851.P12516Q0M604824.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2491, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203474105.P12705Q0M450957.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=1489, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203474330.P12758Q0M302789.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=1483, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203474352.P12765Q0M853382.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=1520, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203475497.P12947Q0M759098.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=1554, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203476420.P13131Q0M140164.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1011, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203477055.P13350Q0M324248.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=1511, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203485834.P14664Q0M678604.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=2153, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203555290.P27989Q0M937789.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=2017, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203566780.P29789Q0M486178.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1570, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1216416810.P17960Q0M786183.tinman:2,S", 
{st_mode=S_IFREG|0600, st_size=1447, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203567387.P29984Q0M463701.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1560, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203568156.P30125Q0M174453.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1570, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203568755.P30222Q0M271021.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1555, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203578404.P31535Q0M370292.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1125, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203581122.P31861Q0M954508.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2108, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203596470.P3307Q0M326986.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=2738, ...}) = 0
getdents64(12, /* 64 entries */, 4096)  = 4096
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203615744.P6582Q0M282341.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2027, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203619209.P7288Q0M583007.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=8739, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203629165.P9049Q0M921642.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=3049, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203638438.P10774Q0M313047.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=8889, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203639137.P10877Q0M554068.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=9549, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203679395.P16427Q0M89616.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1364, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203689732.P20116Q0M93680.scarecrow:2,Sbc", 
{st_mode=S_IFREG|0600, st_size=2440, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203690022.P20155Q0M909689.scarecrow:2,Sbc", 
{st_mode=S_IFREG|0600, st_size=2303, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203693712.P20948Q0M30023.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=3991, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203693933.P20990Q0M934746.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2371, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203695416.P21386Q0M135204.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=6992, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203698879.P21995Q0M135839.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1691, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203700228.P22234Q0M28365.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1013, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203703239.P23143Q0M571200.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2122, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203704119.P23375Q0M653158.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2256, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203713490.P25274Q0M840767.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=19577, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203736413.P29935Q0M732560.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=3143, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203802545.P10420Q0M281614.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2620, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203803404.P10616Q0M912757.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=2622, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203804020.P10721Q0M538580.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=3003, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203805331.P10980Q0M701431.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=2361, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203809386.P25318Q0M128371.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=4004, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203809725.P27021Q0M447783.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=3679, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203813058.P6051Q0M690481.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=816, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203874686.P31025Q0M52827.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=2933, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203892798.P6675Q0M22252.scarecrow:2,RSc", 
{st_mode=S_IFREG|0600, st_size=2357, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203892996.P6750Q0M114883.scarecrow:2,Sc", 
{st_mode=S_IFREG|0600, st_size=1561, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203896197.P7621Q0M934348.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=616, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203896810.P8108Q0M440868.scarecrow:2,RS", 
{st_mode=S_IFREG|0600, st_size=3620, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203900525.P10657Q0M868027.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=6304, ...}) = 0
lstat64("/home/vmail/u13.net/ryan/Maildir/cur/1203902148.P10984Q0M386235.scarecrow:2,S", 
{st_mode=S_IFREG|0600, st_size=3086, ...}) = 0