I'd like to clarify the requirements for the mdb maxsize parameter.
According to the current admin guide:
"This should be the largest that the database is ever anticipated to grow"
Which would seem to imply it cannot later be changed without completely rebuilding the database.
According to the slapd-mdb manpage:
"Note: It is important to set this to as large a value as possible, (relative to anticipated growth of the actual data over time) since growing the size later may not be practical when the system is under heavy load."
It can possibly be changed later, but maybe not ;).
Based on unauthoritative postings I've read, it seems that if you shut down openldap, you can change it to whatever you want, and when you restart openldap, the additional size will immediately be available with no problems. It also seems that if you're using cn=config, you can change it live and it will immediately take effect. I haven't seen any postings indicating a problem that occurred while changing it live.
Are there any restrictions for changing it while the server is down? What restrictions, or problems, if any, are involved when changing it while the server is up?
Thanks much.
--On Tuesday, January 07, 2014 6:46 PM -0800 "Paul B. Henson" henson@acm.org wrote:
I'd like to clarify the requirements for the mdb maxsize parameter.
According to the current admin guide:
"This should be the largest that the database is ever anticipated to grow"
It can possibly be changed later, but maybe not ;)
I change the maxsize of my db all the time, while slapd is running, without issue, as long as the maxsize is not attempted to be set to less than value of the actual size of the DB.
--Quanah
--
Quanah Gibson-Mount Architect - Server Zimbra, Inc. -------------------- Zimbra :: the leader in open source messaging and collaboration
From: Quanah Gibson-Mount [mailto:quanah@zimbra.com] Sent: Wednesday, January 08, 2014 8:20 AM
I change the maxsize of my db all the time, while slapd is running,
without
issue, as long as the maxsize is not attempted to be set to less than
value
of the actual size of the DB.
Cool; thanks for the data point.
Paul B. Henson wrote:
From: Quanah Gibson-Mount [mailto:quanah@zimbra.com] Sent: Wednesday, January 08, 2014 8:20 AM
I change the maxsize of my db all the time, while slapd is running,
without
issue, as long as the maxsize is not attempted to be set to less than
value
of the actual size of the DB.
Cool; thanks for the data point.
I rather thought the manpage was self-explanatory. Put another way - in the middle of a heavy write load when your server is running at 100% utilization is the wrong time to discover that you need to increase the maxsize. A smart admin picks a very large number at init time (e.g. some percentage of the disk partition size) and never has to worry about it again.
From: Howard Chu [mailto:hyc@symas.com] Sent: Wednesday, January 08, 2014 8:19 PM
I rather thought the manpage was self-explanatory.
The man page is reasonably clear, but it does not jibe with the documentation in the admin guide, which adds a degree of confusion, resulting in my inquiry. Perhaps the admin guide documentation could be updated to match the man page?
Thanks.
openldap-technical@openldap.org
-
Howard Chu -
Paul B. Henson -
Quanah Gibson-Mount