> On 30.8.2019 12.33, Gerald Galster via dovecot wrote: >> Hello, >> >> when calling doveadm backup like in the following example, it seems to flush >> every email to disk >> maxing out harddrives (iops) and resulting in very poor performance: >> >> Calling doveadm -o plugin/quota= backup -u "statusma...@domain.com" >> "mdbox:/backup/vmail/domain.com/statusmails" >> finished in 212 secs [changes:1800 copy:1800 delete:0 expunge:0] >> >> The source mdbox holds 1800 small emails and uses about 20 MB disk space >> only. >> >> I've tried -f (full sync) and -l 30 (locking the mailbox) which did not get >> faster, nor did doveadm sync -1. >> >> When using doveadm import all mails are copied in less than 3 seconds: >> time doveadm -o mail=mdbox:/backup/vmail/domain.com/statusmails import >> mdbox:/var/vmail/domain.com/statusmails "" all >> real 0m2.605s >> >> Are there any other options I could try to speed up doveadm backup, avoiding >> the flush after each email? >> >> This is doveadm from dovecot 2.2 (>= 2.2.33). Does anyone get better results >> with 2.3 tree? >> >> Best regards >> Gerald > > Try setting mail_fsync=never
Thanks Aki, that did the trick! Calling /usr/bin/doveadm -o plugin/quota= -o mail_fsync=never backup -u "statusma...@domain.com" "mdbox:/backup/vmail/domain.com/statusmails" finished in 2 secs [changes:1925 copy:1925 delete:0 expunge:0] Best regards Gerald
