> Netstat result:
> $ netstat -tn | sed -n '/:27017.*TIME_WAIT/p' | wc -l
> 28234

> This means mongo client connections leave 28234 sockets in TIME_WAIT. This
> is unacceptable.

> On Saturday, 29 September 2012 02:23:01 UTC+2, Pieter Jordaan wrote:

>> Hi mongodb-user

>> I am using C++ and ScopedDbConnection in a multithreaded environment. For
>> my current testing purposes I have a single machine replica set with a
>> single node. I have high volume writes into the database. I see hundreds of
>> new connections and dropped connections in mongodb's log file. This seems
>> irregular for a connection pool. I am appending the excerpt of the log file
>> for reference. I use it as follows on multiple threads:

>> boost::scoped_ptr<mongo::ScopedDbConnection>
>> connect(mongo::ScopedDbConnection::getScopedDbConnection("myset/
>> 127.0.0.1:27017");
>> ...
>> connect->done();

>> This problem leads to thousands of TIME_WAIT sockets and eventually the
>> client driver and other applications dropping connections with errors like:
>> socket exception [CONNECT_ERROR] for myset/127.0.0.1:27017
>> Is this related to the C++ driver or internals of the mongod process?

>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49893 #688766 (24 connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49894 #688767 (24 connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49895 #688768 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688761] end connection 127.0.0.1:49888 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49896 #688769 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688768] end connection 127.0.0.1:49895 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49897 #688770 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688767] end connection 127.0.0.1:49894 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49898 #688771 (25 connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49899 #688772 (26 connections now open)
>> Sat Sep 29 01:51:13 [conn688765] end connection 127.0.0.1:49892 (25
>> connections now open)
>> Sat Sep 29 01:51:13 [conn688762] end connection 127.0.0.1:49889 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49900 #688773 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688764] end connection 127.0.0.1:49891 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49901 #688774 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688769] end connection 127.0.0.1:49896 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49902 #688775 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688766] end connection 127.0.0.1:49893 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49903 #688776 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688772] end connection 127.0.0.1:49899 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [conn688763] end connection 127.0.0.1:49890 (23
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49904 #688777 (25 connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49905 #688778 (26 connections now open)
>> Sat Sep 29 01:51:13 [conn688778] end connection 127.0.0.1:49905 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [conn688773] end connection 127.0.0.1:49900 (23
>> connections now open)
>> Sat Sep 29 01:51:13 [conn688771] end connection 127.0.0.1:49898 (23
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49906 #688779 (25 connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49907 #688780 (24 connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49908 #688781 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688770] end connection 127.0.0.1:49897 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49909 #688782 (26 connections now open)
>> Sat Sep 29 01:51:13 [conn688774] end connection 127.0.0.1:49901 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49910 #688783 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688780] end connection 127.0.0.1:49907 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49911 #688784 (25 connections now open)
>> Sat Sep 29 01:51:13 [conn688781] end connection 127.0.0.1:49908 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49912 #688785 (26 connections now open)
>> Sat Sep 29 01:51:13 [conn688776] end connection 127.0.0.1:49903 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49913 #688786 (27 connections now open)
>> Sat Sep 29 01:51:13 [conn688782] end connection 127.0.0.1:49909 (24
>> connections now open)
>> Sat Sep 29 01:51:13 [initandlisten] connection accepted from
>> 127.0.0.1:49914 #688787 (26 connections now open)
>> Sat Sep 29 01:51:13 [conn688779] end connection 127.0.0.1:49906 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49915 #688788 (26 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49916 #688789 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688777] end connection 127.0.0.1:49904 (25
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688783] end connection 127.0.0.1:49910 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49917 #688790 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688786] end connection 127.0.0.1:49913 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688788] end connection 127.0.0.1:49915 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49918 #688791 (24 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49919 #688792 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49920 #688793 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688784] end connection 127.0.0.1:49911 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688785] end connection 127.0.0.1:49912 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688775] end connection 127.0.0.1:49902 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49921 #688794 (27 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49922 #688795 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688792] end connection 127.0.0.1:49919 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688787] end connection 127.0.0.1:49914 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49923 #688796 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49924 #688797 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688790] end connection 127.0.0.1:49917 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49925 #688798 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688789] end connection 127.0.0.1:49916 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49926 #688799 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688791] end connection 127.0.0.1:49918 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49927 #688800 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688795] end connection 127.0.0.1:49922 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688793] end connection 127.0.0.1:49920 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49928 #688801 (24 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49929 #688802 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688794] end connection 127.0.0.1:49921 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49930 #688803 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688800] end connection 127.0.0.1:49927 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49931 #688804 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688796] end connection 127.0.0.1:49923 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49932 #688805 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688801] end connection 127.0.0.1:49928 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49933 #688806 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688798] end connection 127.0.0.1:49925 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688799] end connection 127.0.0.1:49926 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49934 #688807 (24 connections now open)
>> Sat Sep 29 01:51:14 [conn688797] end connection 127.0.0.1:49924 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49935 #688808 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49936 #688809 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49937 #688810 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688802] end connection 127.0.0.1:49929 (22
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688805] end connection 127.0.0.1:49932 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49938 #688811 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49939 #688812 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688803] end connection 127.0.0.1:49930 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688804] end connection 127.0.0.1:49931 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49940 #688813 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688807] end connection 127.0.0.1:49934 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49941 #688814 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688806] end connection 127.0.0.1:49933 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49942 #688815 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688810] end connection 127.0.0.1:49937 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688808] end connection 127.0.0.1:49935 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49943 #688816 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49944 #688817 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49945 #688818 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688809] end connection 127.0.0.1:49936 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688811] end connection 127.0.0.1:49938 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49946 #688819 (26 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49947 #688820 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688813] end connection 127.0.0.1:49940 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688815] end connection 127.0.0.1:49942 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688814] end connection 127.0.0.1:49941 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49948 #688821 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49949 #688822 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688816] end connection 127.0.0.1:49943 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49950 #688823 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688812] end connection 127.0.0.1:49939 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688817] end connection 127.0.0.1:49944 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49951 #688824 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49952 #688825 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688818] end connection 127.0.0.1:49945 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49953 #688826 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688821] end connection 127.0.0.1:49948 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49954 #688827 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49955 #688828 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688819] end connection 127.0.0.1:49946 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49956 #688829 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688826] end connection 127.0.0.1:49953 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688823] end connection 127.0.0.1:49950 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49957 #688830 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688820] end connection 127.0.0.1:49947 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49958 #688831 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688827] end connection 127.0.0.1:49954 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688825] end connection 127.0.0.1:49952 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49959 #688832 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49960 #688833 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688822] end connection 127.0.0.1:49949 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49961 #688834 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688829] end connection 127.0.0.1:49956 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688824] end connection 127.0.0.1:49951 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49962 #688835 (24 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49963 #688836 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49964 #688837 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688828] end connection 127.0.0.1:49955 (25
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688831] end connection 127.0.0.1:49958 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49965 #688838 (25 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49966 #688839 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688833] end connection 127.0.0.1:49960 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688832] end connection 127.0.0.1:49959 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49967 #688840 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688830] end connection 127.0.0.1:49957 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49968 #688841 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688837] end connection 127.0.0.1:49964 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49969 #688842 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688835] end connection 127.0.0.1:49962 (25
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49970 #688843 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688839] end connection 127.0.0.1:49966 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49971 #688844 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688836] end connection 127.0.0.1:49963 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49972 #688845 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688838] end connection 127.0.0.1:49965 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49973 #688846 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688841] end connection 127.0.0.1:49968 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49974 #688847 (26 connections now open)
>> Sat Sep 29 01:51:14 [conn688840] end connection 127.0.0.1:49967 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49975 #688848 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688834] end connection 127.0.0.1:49961 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688842] end connection 127.0.0.1:49969 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49976 #688849 (24 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49977 #688850 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688843] end connection 127.0.0.1:49970 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49978 #688851 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688845] end connection 127.0.0.1:49972 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [conn688846] end connection 127.0.0.1:49973 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49979 #688852 (24 connections now open)
>> Sat Sep 29 01:51:14 [conn688844] end connection 127.0.0.1:49971 (23
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49980 #688853 (24 connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49981 #688854 (25 connections now open)
>> Sat Sep 29 01:51:14 [conn688848] end connection 127.0.0.1:49975 (24
>> connections now open)
>> Sat Sep 29 01:51:14 [initandlisten] connection accepted from
>> 127.0.0.1:49982 #688855 (25 connections now open)