Attempting to use a db with approximately 50 collections using 604GB of disk space. Running db.stats() abruptly fails along with clients going into a "waiting" state.

/var/log/mongodb/mongo.log includes the line:
[conn1] getFile(304) _files.size:304 /var/lib/mongodb/preannotation.304

That file doesn't exist:

mongodb@stsia0408:/var/log/mongodb> ls /var/lib/mongodb/preannotation.30*
/var/lib/mongodb/preannotation.30 /var/lib/mongodb/preannotation.301 /var/lib/mongodb/preannotation.303
/var/lib/mongodb/preannotation.300 /var/lib/mongodb/preannotation.302

Wed Jan 15 17:06:30.062 [initandlisten] MongoDB starting : pid=15707 port=27017 dbpath=/var/lib/mongodb 64-bit host=stsia0408
Wed Jan 15 17:06:30.062 [initandlisten] db version v2.4.3
Wed Jan 15 17:06:30.062 [initandlisten] git version: nogitversion
Wed Jan 15 17:06:30.062 [initandlisten] build info: Linux stsia0508 2.6.34-12-desktop #1 SMP PREEMPT 2010-06-29 02:39:08 +0200 x86_64 BOOST_LIB_VERSION=1_49
Wed Jan 15 17:06:30.062 [initandlisten] allocator: tcmalloc
Wed Jan 15 17:06:30.062 [initandlisten] options:

{ config: "/etc/mongodb.conf", dbpath: "/var/lib/mongodb", fork: "true", logappend: "true", logpath: "/var/log/mongodb/mongodb.log", nohttpinterface: "true", oplogSize: 8192, quiet: true }

Wed Jan 15 17:06:30.073 [initandlisten] journal dir=/var/lib/mongodb/journal
Wed Jan 15 17:06:30.073 [initandlisten] recover : no journal files present, no recovery needed
Wed Jan 15 17:06:30.113 [initandlisten] waiting for connections on port 27017
Wed Jan 15 17:06:42.119 [conn1] error: getFile() called in a read lock, yet file to return is not yet open
Wed Jan 15 17:06:42.120 [conn1] getFile(304) _files.size:304 /var/lib/mongodb/preannotation.304
Wed Jan 15 17:06:42.120 [conn1] context ns: preannotation.
Wed Jan 15 17:06:42.120 [conn1] preannotation. Assertion failure false src/mongo/db/database.cpp 300
0xda0006 0xd48e6f 0x8f6577 0x8e2d92 0xa899ae 0x9087d5 0x8fe52f 0x90032a 0x900d1b 0xaa2a8a 0xaa72e4 0xa2d1b1 0x73a131 0xd82520 0x7f65530d0a4f 0x7f6551eaf82d
/usr/sbin/mongod(_ZN5mongo15printStackTraceERSo+0x26) [0xda0006]
/usr/sbin/mongod(_ZN5mongo12verifyFailedEPKcS1_j+0xbf) [0xd48e6f]
/usr/sbin/mongod(_ZN5mongo8Database7getFileEiib+0x317) [0x8f6577]
/usr/sbin/mongod(_ZN5mongo11DataFileMgr9getExtentERKNS_7DiskLocE+0x42) [0x8e2d92]
/usr/sbin/mongod(_ZNK5mongo16NamespaceDetails11storageSizeEPiPNS_16BSONArrayBuilderE+0x1e) [0xa899ae]
/usr/sbin/mongod(_ZN5mongo7DBStats3runERKSsRNS_7BSONObjEiRSsRNS_14BSONObjBuilderEb+0x2d5) [0x9087d5]
/usr/sbin/mongod(_ZN5mongo12_execCommandEPNS_7CommandERKSsRNS_7BSONObjEiRSsRNS_14BSONObjBuilderEb+0x2f) [0x8fe52f]
/usr/sbin/mongod(_ZN5mongo7Command11execCommandEPS0_RNS_6ClientEiPKcRNS_7BSONObjERNS_14BSONObjBuilderEb+0xb4a) [0x90032a]
/usr/sbin/mongod(_ZN5mongo12_runCommandsEPKcRNS_7BSONObjERNS_11_BufBuilderINS_16TrivialAllocatorEEERNS_14BSONObjBuilderEbi+0x5bb) [0x900d1b]
/usr/sbin/mongod(_ZN5mongo11runCommandsEPKcRNS_7BSONObjERNS_5CurOpERNS_11_BufBuilderINS_16TrivialAllocatorEEERNS_14BSONObjBuilderEbi+0x3a) [0xaa2a8a]
/usr/sbin/mongod(ZN5mongo8runQueryERNS_7MessageERNS_12QueryMessageERNS_5CurOpES1+0xce4) [0xaa72e4]
/usr/sbin/mongod(_ZN5mongo16assembleResponseERNS_7MessageERNS_10DbResponseERKNS_11HostAndPortE+0xc91) [0xa2d1b1]
/usr/sbin/mongod(_ZN5mongo16MyMessageHandler7processERNS_7MessageEPNS_21AbstractMessagingPortEPNS_9LastErrorE+0xd1) [0x73a131]
/usr/sbin/mongod(_ZN5mongo17PortMessageServer17handleIncomingMsgEPv+0x480) [0xd82520]
/lib64/libpthread.so.0(+0x6a4f) [0x7f65530d0a4f]
/lib64/libc.so.6(clone+0x6d) [0x7f6551eaf82d]