The Jargon File (version 4.4.7, 29 Dec 2003):

DSW
 n.

    [alt.(sysadmin|tech-support).recovery; abbrev. for Dick Size War] A contest
    between two or more people boasting about who has the faster machine, keys
    on (either physical or cryptographic) keyring, greyer hair, or almost
    anything. Salvos in a DSW are typically humorous and playful, often
    self-mocking.


The Free On-line Dictionary of Computing (30 December 2018):

penis war
Dick Size War
DSW
IRC penis war

    (Or "Dick Size War", "DSW") Any argument which
   has degenerated into quantitative boasting of the sort "My
   [program|bot|etc.] is [faster|meaner|etc.]  than yours!".
   Generally as unconstructive (and with as little emphasis on
   empirical proof) as men debating who has the biggest penis.

   The term is often used on IRC, news:alt.sysadmin.recovery,
   and sometimes applied to IRC botwars, because of their
   equally pointless nature.

   (1999-07-14)