If you are using Veritas NetBackup on Solaris 9 with LTO Ultrium-2 tape drives, you will be constantly annoyed by slow tape write performance unless you use blocks of at least 256KB.
To resolve this, the first thing you’ll want to do is increase both the number of buffers and the buffer size on the media manager host:
Create and edit the file: /usr/openv/netbackup/db/config/SIZE_DATA_BUFFERS and add 262144 on the first line.
Create and edit the file: /usr/openv/netbackup/db/config/NUMBER_DATA_BUFFERS and add 16 on the first line.
These numbers with their respective quotes should be the only thing in these two files.
Next, since Solaris still has insanely low limits on its default shared memory subsystem, we have to increase these limits as to not exhaust them with the increased NetBackup Buffer sizes. We do this by editing the /etc/system file and adding the following lines.
set msgsys:msginfo_msgmni=1024
set msgsys:msginfo_msgtql=1024
set semsys:seminfo_semmni=2048
set semsys:seminfo_semmns=2048
set semsys:seminfo_semopm=128
set shmsys:shminfo_shmmax=33554432
set shmsys:shminfo_shmmni=512
It is now necessary to reboot the system for the kernel parameters to become active.
You should now notice a dramatic increase in tape write speed during your backups.
Actually these paramaters should be added without quotes.
That is correct… I added the quotes because I thought it would be made more clear, but upon re-reading it, I realize that it could cause confusion… I will remove the quotes around the numbers from the original post. Thanks for the catch.
I think I meant to write “without the quotes”, but made an error. Thanks again for the catch.
I am having slow backup speeds using netbackup6 with solaris 10 and lto3 drives. Will this work in my scenario. I am currently getting 10000KB/SEC all FC connections.
This looks like it could resolve a slowness complaint we have having for years from our backup admin.
One question… The system file on our Solaris 9 media server looks lik this (See below) do I remove what is currently in the file and add the lines you mention in this blog or just update the relevant paramaters and leave the other lines?
* Message queues
set msgsys:msginfo_msgmap=500
set msgsys:msginfo_msgmax=8192
set msgsys:msginfo_msgmnb=65536
set msgsys:msginfo_msgmni=256
set msgsys:msginfo_msgssz=32
set msgsys:msginfo_msgtql=500
set msgsys:msginfo_msgseg=8192
* Semaphores
set semsys:seminfo_semmap=64
set semsys:seminfo_semmni=1024
set semsys:seminfo_semmns=1024
set semsys:seminfo_semmnu=1024
set semsys:seminfo_semmsl=300
set semsys:seminfo_semopm=32
set semsys:seminfo_semume=64
* Shared memory
set shmsys:shminfo_shmmax=16777216
set shmsys:shminfo_shmmin=1
set shmsys:shminfo_shmmni=230
set shmsys:shminfo_shmseg=100