The following log messages are generally not very clear, useful, or consistent.

• closest to what? What's the context? Should be more verbose.

  is now closest at
      master: in src/mongo/db/repl/health.cpp:410
  

• We should better explain what this means here rather than referring to a cryptic internal term.

  Using idhack:
      master: in src/mongo/db/query/get_runner.cpp:127
      master: in src/mongo/db/query/get_runner.cpp:227
  

• On log level 0, this is not very useful to users. Should explain what the actual problem is.

  info openExisting file size <var> but storageGlobalParams.smallfiles=false:
      master: in src/mongo/db/storage/data_file.cpp:105
  

• Not a proper sentence. Should also use either "collection scan" or "COLLSCAN" like $explain does.

  collection dropped during yield of collscan or state deleted
      master: in src/mongo/db/exec/collection_scan.cpp:140
  

• Why are we about to fassert? What is the actual problem? We'll see the fassert in the log anyway.

  about to fassert - <var> numIndexesTotal(): <var> numSystemIndexesEntries: <var> _entries.size(): <var> indexNamesToDrop: <var> haveIdIndex:
      master: in src/mongo/db/catalog/index_catalog.cpp:761
  

• There is an almost identical log message at src/mongo/db/mongod_options.cpp:653 with just 1 space less. Should make them consistent.

  **          enabling http interface
      master: in src/mongo/db/mongod_options.cpp:628
  

• Seek of what? This should be more detailed, since seek is a very overloaded term.

  Seek failed:
      master: in src/mongo/db/exec/index_scan.cpp:97
  

• almost identical message but without ** at src/mongo/util/processinfo_linux2.cpp:450, is this on purpose?

  ** WARNING: Cannot detect if NUMA interleaving is enabled. <var> Failed to probe \ <var> \
      master: in src/mongo/db/startup_warnings.cpp:95
  

• Needs to be removed or changed to something meaningful in both places. We can't have a "uh oh" as a log level 0 message.

  uh oh:
      master: in src/mongo/db/index/index_descriptor.h:164
      master: in src/mongo/db/storage/extent_manager.cpp:108
  

• "bg" should be replaced with "background", and the (ok) part should be fleshed out a bit more.

  info: key already in index during bg indexing (ok)
      master: in src/mongo/db/index/btree_based_access_method.cpp:83
  

• "params" should be "parameters". If this is an "ERROR", should it use the error() macro instead?

  ERROR: No authentication params set for internal user
      master: in src/mongo/db/auth/security_key.cpp:65
  

• Should clarify what kind of error and what went wrong

                  warning() << "Planner error trying to build geo bounds for " << elt.toString()
                            << " index element.";
  
             warning() << "Planner error, trying to build bounds for expr "
  master: in src/mongo/db/query/index_bounds_builder.cpp:541
  

• This message is a result of an exception. Does the exception have any information about the problem? If so, we should print it out

  warning() << "index rebuilding did not complete" << endl;
      master: in src/mongo/db/index_rebuilder.cpp:70