README-LINUX

If you want readprofile data, you need to give the database user sudo access
to run readprofile.  Root privileges are required to clear the counter data.
Here is an example of passwordless access for user 'postgres' to run
'readprofile -r':

postgres ALL = NOPASSWD: /usr/sbin/readprofile -r

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The number of open files will likely need to be raised for the on the systems
that are driving the database.  

To increase this for a user edit '/etc/security/limits.conf'.  Here is an
example for the user 'postgres':

postgres         soft    nofile          40000
postgres         hard    nofile          40000


The Linux kernel parameter also needs to be adjusted because the user limits
cannot be set above the operating system limits.  Edit '/etc/sysctl.conf':

fs.file-max = 40000


This can be verified in '/proc/sys/fs/file-max'.


Additionally the driver for this workload may need to create more threads
than allowed by default.  To increase the thread per process limit for the
user in '/etc/security/limits.conf':

postgres         soft    nproc           32768
postgres         hard    nproc           32768


Similarly in '/etc/sysctl.conf' for the same reasons as above:

kernel.threads-max = 32768


This can be verified in '/proc/sys/kernel/threads-max'.

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One of the shared memory parameters will likely needs to be raised on the
database system in order to accomidate increasing the shared_buffers parameter
in PostgreSQL.  One way to do this permanently is to edit /etc/sysctl.conf and
add:

kernel.shmmax = 41943040