[LISTSERV - the mailing list management classic]

LISTSERV Top 20 statistics – November 2021


There are many possible ways to measure the relative "importance" or "size" of LISTSERV sites: number of lists, number of subscribers, number of messages delivered, etc. In most cases, the number of messages delivered is used to rank mailing list managers, because it is the most accurate measurement of the amount of activity on the server. But, depending on what you are looking for, other variables may be more appropriate. There are currently three LISTSERV "Top 20" lists, ranking the various servers according to:

In addition, you can view a list of the Top 20 lists in the network (by number of subscribers).

What do these numbers mean exactly?

The statistics are gathered daily by a monitor at L-Soft which polls all the LISTSERV sites that participate in the "open" LISTSERV network over the worldwide Internet. Corporate servers operating in a "closed" environment are not included.

The statistics are organized in monthly reports. The message volume figures are a flat average of the accumulated traffic for the entire month. Thus, a server that delivers 300,000 messages per month will show a daily average of 10,000 messages. In practice, there is a lot less traffic during the weekend, and even during business days there can be significant fluctuations (~30%). The list statistics (number of lists, number of subscribers, largest lists in the network) are measured as of the last day in the month.

For the current month, the message volume figures are averaged based on the number of days that have elapsed. In practice, the figures are not very meaningful in the first few days, especially if the month starts on a weekend. In that case it is best to refer to the previous month for more accurate figures.

A fourth "Top 20" list is available for the more technically oriented: Number of messages generated by the server. This corresponds to the number of mail messages created by the server while processing postings to its mailing lists. LISTSERV delivers its mail using an intelligent mail delivery function called DISTRIBUTE, which improves mail delivery times and reduces bandwidth usage by spreading the delivery chore over scores of participating servers. Each of these servers processes the recipients for its service area (typically its organization or campus). In most cases, DISTRIBUTE simply alters the manner in which the mail is delivered, and the number of messages forwarded to other sites for optimized delivery is roughly equal to the number of messages received by other sites for the same purpose. In some cases, however, this is not the case, either because the server elected to serve a much wider service area than its own organization, or because it is explicitly forwarding all its deliveries to another machine (for instance, many mainframe-based servers forward their mail to a workstation or PC for delivery).


Top 20 sites by volume delivered daily (NOV21, 1-26)

Pos Recipients  Site
--- ----------  ----
  1    1076656  LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition)
  2     888376  JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition)
  3     418878  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  4     388432  LISTS.PSU.EDU (Linux 3.10.0)
  5     287395  LISTES.ULAVAL.CA (Linux 3.10.0)
  6     284062  LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition)
  7     244598  DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.42.2.el7.x86_64)
  8     210209  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  9     205627  LISTS.HAWAII.EDU (Linux 3.10.0-1160.45.1.el7.x86_64)
 10     193507  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 11     187481  LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64)
 12     186480  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 13     181403  LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
 14     168311  LISTS.UFL.EDU (Linux 2.6.32)
 15     155170  LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition)
 16     141903  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 17     141705  LISTSERV.UTORONTO.CA (Linux 3.10.0)
 18     141477  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 19     120809  LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition)
 20     109576  LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)

Top 20 sites by number of subscribers (26 Nov 2021)

Pos Subscribers  Site
--- -----------  ----
  1     5080839  LISTS.PSU.EDU (Linux 3.10.0)
  2     4650505  LISTES.ULAVAL.CA (Linux 3.10.0)
  3     1777535  LISTSERV.TAU.AC.IL (Linux 2.6.9)
  4     1732790  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  5     1502957  LISTSERV.UTORONTO.CA (Linux 3.10.0)
  6     1244951  LISTSERV.TAMU.EDU (Linux 3.0.101)
  7     1073364  LISTS.WAYNE.EDU (Linux 2.6.32)
  8     1059036  LISTS.UFL.EDU (Linux 2.6.32)
  9     1044264  LISTSERV.UA.EDU (Linux 4.12.14)
 10     1036018  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 11     1035028  LIST.MSU.EDU (Linux 3.10.0)
 12      931581  LISTS.UMN.EDU (Linux 3.10.0)
 13      879394  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 14      864662  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 15      853488  LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 16      844771  LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
 17      840809  LISTSERV.UH.EDU (Linux 3.10.0)
 18      806520  LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition)
 19      693420  LISTSERV.LIV.AC.UK (Linux 3.10.0)
 20      679167  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)

Top 20 sites by number of lists (26 Nov 2021)

Pos Lists  Site
--- -----  ----
  1 27937  LISTES.ULAVAL.CA (Linux 3.10.0)
  2 16531  LISTS.PSU.EDU (Linux 3.10.0)
  3 14174  LISTSERV.TAU.AC.IL (Linux 2.6.9)
  4  9788  LISTS.CLEMSON.EDU (Linux 2.6.18)
  5  9599  LISTS.UFL.EDU (Linux 2.6.32)
  6  8079  LISTSERV.TECHNION.AC.IL (Linux 2.6.32)
  7  7115  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  8  6763  LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
  9  6126  LISTSERV.UTORONTO.CA (Linux 3.10.0)
 10  5159  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
 11  4987  LISTSERV.TAMU.EDU (Linux 3.0.101)
 12  4813  LISTS.UMN.EDU (Linux 3.10.0)
 13  4404  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 14  4231  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 15  3799  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 16  3748  LISTS.QUEENSU.CA (Linux 3.10.0)
 17  3414  LISTSERV.BROWN.EDU (Linux 3.10.0)
 18  3393  LIST.UVM.EDU (Linux 2.6.32)
 19  3283  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 20  2772  LISTSERV.KENT.EDU (Windows Server 2012 R2 Standard x64 Edition)

Top 20 sites by volume generated daily (NOV21, 1-26)

Pos Recipients  Site
--- ----------  ----
  1    1074907  LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition)
  2     855228  JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition)
  3     411037  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  4     385049  LISTS.PSU.EDU (Linux 3.10.0)
  5     287177  LISTES.ULAVAL.CA (Linux 3.10.0)
  6     244382  DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.42.2.el7.x86_64)
  7     205933  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  8     203413  LISTS.HAWAII.EDU (Linux 3.10.0-1160.45.1.el7.x86_64)
  9     190070  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 10     185197  LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64)
 11     181168  LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
 12     166449  LISTS.UFL.EDU (Linux 2.6.32)
 13     154956  LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition)
 14     141510  LISTSERV.UTORONTO.CA (Linux 3.10.0)
 15     139320  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 16     138409  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 17     137293  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 18     107299  LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
 19      99768  LISTSERV.ICORS.ORG (Windows Server 2012 R2 Datacenter x64 Edition)
 20      98328  LISTSERV.UA.EDU (Linux 4.12.14)

Top 20 lists by number of subscribers (26 Nov 2021)

Pos Subscribers  Site
--- -----------  ----
  1       59182  CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  2       54050  AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0)
  3       42431  SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition)
  4       41816  OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14)
  5       39354  SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  6       34587  TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition)
  7       33848  CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0)
  8       31621  TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9)
  9       30228  UG2021FALL@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
 10       28887  TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9)
 11       28755  HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
 12       28279  L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0)
 13       27706  RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
 14       27479  TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9)
 15       27381  VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0)
 16       27348  UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0)
 17       26421  PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101)
 18       24992  NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0)
 19       24633  ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)
 20       24288  EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)