[LISTSERV - the mailing list management classic]

LISTSERV Top 20 statistics – 25 May 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 (MAY21, 1-25)

Pos Recipients  Site
--- ----------  ----
  1     832580  JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition)
  2     618308  LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition)
  3     405842  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  4     286349  LISTS.PSU.EDU (Linux 3.10.0)
  5     220407  LISTSERV.TAMU.EDU (Linux 3.0.101)
  6     208532  LIST.UNM.EDU (Linux 3.10.0-1160.25.1.el7.x86_64)
  7     204596  LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
  8     201865  DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.21.1.el7.x86_64)
  9     197578  LISTSERV.ACM.ORG (Windows Server 2012 R2 Datacenter x64 Edition)
 10     178914  LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64)
 11     172218  LISTES.ULAVAL.CA (Linux 3.10.0)
 12     152965  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 13     149510  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 14     149422  LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
 15     133498  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 16     131212  LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
 17     124588  LISTS.UFL.EDU (Linux 2.6.32)
 18     120248  MASSMAIL.VCU.EDU (Windows Server 2012 R2 Datacenter x64 Edition)
 19     119796  LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition)
 20     113383  LIST.UVM.EDU (Linux 2.6.32)

Top 20 sites by number of subscribers (25 May 2021)

Pos Subscribers  Site
--- -----------  ----
  1     4923594  LISTS.PSU.EDU (Linux 3.10.0)
  2     4493917  LISTES.ULAVAL.CA (Linux 3.10.0)
  3     2312293  LS.KULEUVEN.BE (Linux 2.6.32)
  4     1766726  LISTSERV.TAU.AC.IL (Linux 2.6.9)
  5     1625669  LISTSERV.UGA.EDU (Linux 2.6.32)
  6     1239306  LISTS.WAYNE.EDU (Linux 2.6.32)
  7     1195395  LISTSERV.TAMU.EDU (Linux 3.0.101)
  8     1158404  LISTSERV.UTORONTO.CA (Linux 3.10.0)
  9     1130208  LISTSERV.UA.EDU (Linux 4.12.14)
 10     1071739  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 11     1059036  LISTS.UFL.EDU (Linux 2.6.32)
 12      934936  LISTS.UMN.EDU (Linux 3.10.0)
 13      854673  LISTSERV.UTA.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 14      829325  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 15      826997  LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 16      824397  LISTSERV.ECU.EDU (Windows Server 2016 Standard x64 Edition)
 17      793445  LISTSERV.UH.EDU (Linux 3.10.0)
 18      752987  LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
 19      694320  LISTSERV.LIV.AC.UK (Linux 3.10.0)
 20      670120  LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition)

Top 20 sites by number of lists (25 May 2021)

Pos Lists  Site
--- -----  ----
  1 27783  LISTES.ULAVAL.CA (Linux 3.10.0)
  2 17075  LISTS.PSU.EDU (Linux 3.10.0)
  3 14167  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  7595  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  8  6742  LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
  9  5800  LISTSERV.UTORONTO.CA (Linux 3.10.0)
 10  5384  LS.KULEUVEN.BE (Linux 2.6.32)
 11  5001  LISTSERV.TAMU.EDU (Linux 3.0.101)
 12  4959  LISTSERV.UGA.EDU (Linux 2.6.32)
 13  4872  LISTS.UMN.EDU (Linux 3.10.0)
 14  4512  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 15  4305  LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 16  4235  LISTS.QUEENSU.CA (Linux 3.10.0)
 17  3794  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 18  3582  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 19  3367  LIST.UVM.EDU (Linux 2.6.32)
 20  3345  LISTSERV.BROWN.EDU (Linux 3.10.0)

Top 20 sites by volume generated daily (MAY21, 1-25)

Pos Recipients  Site
--- ----------  ----
  1     800549  JISCMAIL.AC.UK (Windows Server 2019 Standard x64 Edition)
  2     617198  LIST.ETSI.ORG (Windows Server 2016 Datacenter x64 Edition)
  3     397540  LISTSERV.LIV.AC.UK (Linux 3.10.0)
  4     282883  LISTS.PSU.EDU (Linux 3.10.0)
  5     216198  LISTSERV.TAMU.EDU (Linux 3.0.101)
  6     208320  LIST.UNM.EDU (Linux 3.10.0-1160.25.1.el7.x86_64)
  7     201670  DISCUSSIONS.EQ.EDU.AU (Linux 3.10.0-1160.21.1.el7.x86_64)
  8     176681  LISTSERV.REDIRIS.ES (Linux 2.6.32-504.3.3.el6.x86_64)
  9     171974  LISTES.ULAVAL.CA (Linux 3.10.0)
 10     150899  LISTSERV.NODAK.EDU (Windows Server 2019 Standard x64 Edition)
 11     147459  LSV.UKY.EDU (Windows Server 2019 Datacenter x64 Edition)
 12     146593  LISTSERV.DARTMOUTH.EDU (Windows Server 2016 Datacenter x64 Edition)
 13     134993  LISTSERV.SYR.EDU (Windows Server 2008 R2 Enterprise x64 Edition)
 14     131013  LISTSERV.UIC.EDU (Linux 2.6.32-504.8.1.el6.x86_64)
 15     129206  LISTSERV.BUFFALO.EDU (Linux 3.10.0)
 16     123098  LISTS.UFL.EDU (Linux 2.6.32)
 17     119596  LISTSERV.UCONN.EDU (Windows Server 2012 R2 Standard x64 Edition)
 18     111927  LIST.UVM.EDU (Linux 2.6.32)
 19     109744  LISTSERV.UA.EDU (Linux 4.12.14)
 20      98742  LISTSERV.AAP.ORG (Windows Server 2012 R2 Standard x64 Edition)

Top 20 lists by number of subscribers (25 May 2021)

Pos Subscribers  Site
--- -----------  ----
  1       59226  CAREERCENTERUPDATE@LISTSERV.UGA.EDU (Linux 2.6.32)
  2       54050  AMIS-CNRS-INTERNATIONAL-L@IN2P3.FR (Linux 3.10.0)
  3       41812  OPSWNEWS@LISTSERV.NYSED.GOV (Linux 4.12.14)
  4       39934  SAFETYNOTICE@LISTSERV.UC.EDU (Windows Server 2019 Datacenter x64 Edition)
  5       34587  TCUATHLETICSDIRECTOR@LISTSERV.TCU.EDU (Windows Server 2012 R2 Standard x64 Edition)
  6       33996  CMU-BASKETBALL@LS2.CMICH.EDU (Linux 3.10.0)
  7       33558  L-SMEAL-REPORT@LISTS.PSU.EDU (Linux 3.10.0)
  8       32013  TAU-STU-ACADEMICSEC-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9)
  9       30835  FOCIS_GROUP@LISTS.WAYNE.EDU (Linux 2.6.32)
 10       29093  TAU-INNOVTL-ALL-STUDENTS@LISTSERV.TAU.AC.IL (Linux 2.6.9)
 11       28918  BEDRIJVENLIJST@LS.KULEUVEN.BE (Linux 2.6.32)
 12       28918  BEDRIJVENLIJST2@LS.KULEUVEN.BE (Linux 2.6.32)
 13       28295  L-THON-NEWS@LISTS.PSU.EDU (Linux 3.10.0)
 14       28089  HALLCOLIBRARY-L@LISTSERV.UGA.EDU (Linux 2.6.32)
 15       27707  RECREATION@LISTSERV.MIAMIOH.EDU (Windows Server 2016 Standard x64 Edition)
 16       27479  TAU4U@LISTSERV.TAU.AC.IL (Linux 2.6.9)
 17       27390  VOLUPDATE@LISTSERV.UTK.EDU (Linux 3.10.0)
 18       26419  PARENTS@LISTSERV.TAMU.EDU (Linux 3.0.101)
 19       25562  ISMA@LS.KULEUVEN.BE (Linux 2.6.32)
 20       24992  NCHPAD-NEWS@LISTSERV.UAB.EDU (Linux 3.10.0)