After my first summary some days ago I received a clarification from Dr. Thomas
Blinn regarding the time stamps.
Tom wrote:
I was mistaken in my belief that the time stamps will cause the log file
to grow quickly. In fact, the new stamps over-write the existing ones,
when the last record in the file is the time stamp. Here's the way it
really works, as explained by the engineer who implemented it:
------- Forwarded Message
It is true that keep-alive timestamps were added to binlogd, regardless
of the architecture of the system on which it is running. However, the
"eaten disk space" is very small. On a non-EV6 system that uses the
original binary.errlog headers, a timestamp record adds 64 bytes to the
file (including the header). Every ten minutes the binlogd:
a) reads in the last record
b) sees if the last record written was a timestamp
c1) if it was a timestamp (the usual case), it OVERWRITES that record
with a new timestamp, so the binary.errlog file size is exactly the same
c2) if the last record was NOT a timestamp, it will write a new one and
add 64 bytes to the size of the file.
Eventually all records will have the new header. I decided not to
special-case the timestamp by architecture because of the negligible
change in size.
------- End of Forwarded Message
Thanks again to Tom for his tribute to this list.
Regards
Peter
Received on Wed Mar 24 1999 - 15:17:49 NZST