We have a server with mongodb and apache2. Yesterday started to log these assertations that mainly occurs when in rockmongo i want to get the one of the db's collections, but i see in the log files that its occurs on 'normal' connections.

Fri Dec 2 08:44:07 [conn1631] authenticate:

{ authenticate: 1, user: "--", nonce: "--", key: "--" }

Fri Dec 2 08:44:08 [conn1631] authenticate:

{ authenticate: 1, user: "--", nonce: "--", key: "--" }

Fri Dec 2 08:44:08 [conn1631] command local.$cmd command: { $eval: CodeWScope( function ()

{ return db.getCollectionNames(); }, {}), args: {} } ntoreturn:1 reslen:50 16ms
Fri Dec 2 08:44:08 [conn1631] profile: warning ns local.system.profile does not exist
Fri Dec 2 08:44:08 [conn1631] command admin.$cmd command: { $eval: CodeWScope( function (){ return db.getCollectionNames(); }

, {}), args: {} } ntoreturn:1 reslen:92 15ms
Fri Dec 2 08:44:08 [conn1631] command tuner_db.$cmd command: { $eval: CodeWScope( function ()

{ return db.getCollectionNames(); }

, {}), args: {} } ntoreturn:1 reslen:864 16ms
Fri Dec 2 08:44:08 [conn1631] tuner_db Assertion failure !loc.isNull() db/pdfile.cpp 1881
0x57eeb6 0x589d6b 0x8a2746 0x777a3e 0x8890d4 0xa9c576 0x638937 0x7ffbf8332efc 0x7ffbf78cc89d
/usr/bin/mongod(_ZN5mongo12sayDbContextEPKc+0x96) [0x57eeb6]
/usr/bin/mongod(_ZN5mongo8assertedEPKcS1_j+0xfb) [0x589d6b]
/usr/bin/mongod() [0x8a2746]
/usr/bin/mongod(_ZN5mongo7profileERKNS_6ClientERNS_5CurOpE+0xc1e) [0x777a3e]
/usr/bin/mongod(_ZN5mongo16assembleResponseERNS_7MessageERNS_10DbResponseERKNS_11HostAndPortE+0xa04) [0x8890d4]
/usr/bin/mongod(_ZN5mongo16MyMessageHandler7processERNS_7MessageEPNS_21AbstractMessagingPortEPNS_9LastErrorE+0x76) [0xa9c576]
/usr/bin/mongod(_ZN5mongo3pms9threadRunEPNS_13MessagingPortE+0x287) [0x638937]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x7efc) [0x7ffbf8332efc]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x6d) [0x7ffbf78cc89d]
Fri Dec 2 08:44:08 [conn1631] AssertionException handling request, closing client connection: 0 assertion db/pdfile.cpp:1881

.
.
.

Fri Dec 2 08:52:30 [conn1611] authenticate:

{ authenticate: 1, user: "--", nonce: "--", key: "--" }

Fri Dec 2 08:52:33 [conn1611] authenticate:

{ authenticate: 1, user: "--", nonce: "--", key: "--" }

Fri Dec 2 08:52:33 [conn1611] command tuner_db.$cmd command:

{ authenticate: 1, user: "--", nonce: "--", key: "--" }

ntoreturn:1 reslen:37 17ms
Fri Dec 2 08:52:33 [conn1611] tuner_db Assertion failure !loc.isNull() db/pdfile.cpp 1881
0x57eeb6 0x589d6b 0x8a2746 0x777a3e 0x8890d4 0xa9c576 0x638937 0x7ffbf8332efc 0x7ffbf78cc89d
/usr/bin/mongod(_ZN5mongo12sayDbContextEPKc+0x96) [0x57eeb6]
/usr/bin/mongod(_ZN5mongo8assertedEPKcS1_j+0xfb) [0x589d6b]
/usr/bin/mongod() [0x8a2746]
/usr/bin/mongod(_ZN5mongo7profileERKNS_6ClientERNS_5CurOpE+0xc1e) [0x777a3e]
/usr/bin/mongod(_ZN5mongo16assembleResponseERNS_7MessageERNS_10DbResponseERKNS_11HostAndPortE+0xa04) [0x8890d4]
/usr/bin/mongod(_ZN5mongo16MyMessageHandler7processERNS_7MessageEPNS_21AbstractMessagingPortEPNS_9LastErrorE+0x76) [0xa9c576]
/usr/bin/mongod(_ZN5mongo3pms9threadRunEPNS_13MessagingPortE+0x287) [0x638937]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x7efc) [0x7ffbf8332efc]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x6d) [0x7ffbf78cc89d]
Fri Dec 2 08:52:33 [conn1611] AssertionException handling request, closing client connection: 0 assertion db/pdfile.cpp:1881

The differencies in mongodb.conf are the followings:
profile=1
slowms=10
nojournal=true
logappend=true
auth=true
noprealloc=true

Its a single mongodb instance, no relicas or sharding.
Current connections are around 30, with some query and update here and there, so there not so much load on mongodb(right now).