[LISTSERV - the mailing list management classic]

LISTSERV Top 20 statistics – December 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 (DEC21, 1-23)

Pos Recipients  Site
--- ----------  ----
  1     738944  JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition)
  2     358262  LISTS.PSU.EDU (Linux 3.10.0)
  3     341209  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  4     291920  LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition)
  5     249079  LISTS.HAWAII.EDU (Linux 3.10.0-1160.45.1.el7.x86_64)
  6     235091  LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition)
  7     186045  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
  8     182868  LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64)
  9     176880  LISTES.ULAVAL.CA (Linux 3.10.0)
 10     172194  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
 11     161255  LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition)
 12     160132  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 13     160081  LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
 14     153632  LISTS.UFL.EDU (Linux 2.6.32)
 15     131321  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 16     120821  LISTS.ROCHESTER.EDU (Windows Server 2012 R2 Standard x64 Edition)
 17     119788  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 18     117578  LISTSERV.WUSTL.EDU (Windows Server 2016 Standard x64 Edition)
 19     110728  DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.45.1.el7.x86_64)
 20     106462  MASSMAIL.VCU.EDU (Windows Server 2012 R2 Datacenter x64 Edition)

Top 20 sites by number of subscribers (23 Dec 2021)

Pos Subscribers  Site
--- -----------  ----
  1     5560895  LISTES.ULAVAL.CA (Linux 3.10.0)
  2     5081078  LISTS.PSU.EDU (Linux 3.10.0)
  3     1777535  LISTSERV.TAU.AC.IL (Linux 2.6.9)
  4     1691123  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  5     1492287  LISTSERV.UTORONTO.CA (Linux 3.10.0)
  6     1254578  LISTSERV.TAMU.EDU (Linux 3.0.101)
  7     1086228  LISTSERV.UA.EDU (Linux 4.12.14)
  8     1059533  LISTS.WAYNE.EDU (Linux 2.6.32)
  9     1059036  LISTS.UFL.EDU (Linux 2.6.32)
 10     1030832  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 11      938103  LIST.MSU.EDU (Linux 3.10.0)
 12      934418  LISTS.UMN.EDU (Linux 3.10.0)
 13      869185  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 14      863281  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 15      853488  LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 16      842796  LISTSERV.UH.EDU (Linux 3.10.0)
 17      837282  LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition)
 18      828688  LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
 19      698197  LISTSERV.LIV.AC.UK (Linux 3.10.0)
 20      685953  LISTS.QUEENSU.CA (Linux 3.10.0)

Top 20 sites by number of lists (23 Dec 2021)

Pos Lists  Site
--- -----  ----
  1 34479  LISTES.ULAVAL.CA (Linux 3.10.0)
  2 16537  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  7130  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  8  6764  LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
  9  6143  LISTSERV.UTORONTO.CA (Linux 3.10.0)
 10  5162  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
 11  4987  LISTSERV.TAMU.EDU (Linux 3.0.101)
 12  4799  LISTS.UMN.EDU (Linux 3.10.0)
 13  4416  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 14  4236  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 15  3810  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 16  3752  LISTS.QUEENSU.CA (Linux 3.10.0)
 17  3424  LISTSERV.BROWN.EDU (Linux 3.10.0)
 18  3393  LIST.UVM.EDU (Linux 2.6.32)
 19  3286  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 (DEC21, 1-23)

Pos Recipients  Site
--- ----------  ----
  1     708199  JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition)
  2     355324  LISTS.PSU.EDU (Linux 3.10.0)
  3     333711  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  4     291273  LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition)
  5     247654  LISTS.HAWAII.EDU (Linux 3.10.0-1160.45.1.el7.x86_64)
  6     180663  LISTSERV.REDIRIS.ES (Linux 3.10.0-1062.9.1.el7.x86_64)
  7     176709  LISTES.ULAVAL.CA (Linux 3.10.0)
  8     168364  LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  9     161010  LISTSERV.UCONN.EDU (Windows Server 2019 Datacenter x64 Edition)
 10     159895  LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
 11     156988  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 12     152084  LISTS.UFL.EDU (Linux 2.6.32)
 13     129384  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 14     122146  LISTSERV.SYR.EDU (Windows Server 2019 Standard x64 Edition)
 15     115063  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 16     110627  DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.45.1.el7.x86_64)
 17     103816  LISTSERV.UTORONTO.CA (Linux 3.10.0)
 18     101787  LISTSERV.UA.EDU (Linux 4.12.14)
 19      96632  LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition)
 20      94942  LISTS.WAYNE.EDU (Linux 2.6.32)

Top 20 lists by number of subscribers (23 Dec 2021)

Pos Subscribers  Site
--- -----------  ----
  1       54050  AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0)
  2       41817  OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14)
  3       40427  SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition)
  4       39353  SUCCESS@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  5       34587  TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition)
  6       33791  CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0)
  7       31621  TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9)
  8       30227  UG2021FALL@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
  9       28887  TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9)
 10       28647  HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Windows Server 2016 Datacenter x64 Edition)
 11       28277  L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0)
 12       27706  RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
 13       27479  TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9)
 14       27381  VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0)
 15       27348  UTENNSRP@LISTSERV.UTK.EDU (Linux 3.10.0)
 16       26421  PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101)
 17       24992  NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0)
 18       24633  ECF-MIWD@NYED.USCOURTS.GOV (Linux 3.10.0)
 19       24288  EXCEL@LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 20       22770  STUDENT-TRAVEL-SURVEY-L@LISTSERV.OKSTATE.EDU (Windows Server 2012 Datacenter x64 Edition)