MemSQL CentOs 6.4 Installation issue - centos

I have Installed and worked with MemSQL on Ubuntu 12.04 and CentOS 6. But I am doing a fresh install on CentOs 6.4 (FInal). When running ./check_system script I am getting the following error.
Warning: The number of allowed open file descriptors should be at least 64000. This OS is currently configured with the limit set to 1024. Please visit http://developers.memsql.com/docs/2.5/admin/admin_concepts.html#configuring-the-linux-file-descriptor-limit
./check_system: line 313: 6173 Illegal instruction (core dumped) $SCRIPT_DIR/lib/check_crc32 > /dev/null 2> /dev/null
Warning: SSE4.2 is not supported. Resorting to software CRC32C. MemSQL recovery and log writing performance will be negatively impacted.
I am familiar with the warning and I know how to fix it. its the Illegal instructions error I am trying to understand.
Any help in this regard will be useful.

For the file descriptor warning, you can either read that link, or simply use the rpm or deb package to install - both of these will configure that limit for you.
The warning about SSE4.2 is not a fatal warning - the server will run fine, generally with single-digit percentage slowdown to insert and update queries.

Read, Installation Best Practices HOWTO:
http://docs.memsql.com/latest/setup/best_practices/#increase-file-descriptor-limit
Also try restart svr

Related

Red Hat needs-restarting

I have some problems trying to test "needs-restarting -r ; echo $?" inside a RedHat distribution. The command works for cases where a reboot is not required, but I have not been able to voluntarily generate the need to reboot in the operating system, which has made it impossible for me to know if the response to the command works. That is to say the output in 1 of the needs-restarting. Do you know of any way to generate the need to reboot in a controlled manner in RedHat?
You can find which packages require a system reboot after the update to Redhat KB. If you can downgrade one of these packages, you can generate reboot required state. But this is not recommended in production systems. glibc and kernel downgrades can cause problems. You can try it at new installed Rhel server after "yum update".

Sophos for Ubuntu blocking Flatpak application installs

I have installed Sophos for Ubuntu and it has been working fairly well until I decided to try Flatpak.
When installing or updating anything using Flatpak, I now get this pop up:
error popup
with this corresponding error on the terminal:
********************** Sophos Anti-Virus Alert *****************
Error scanning file
"/var/tmp/flatpak-cache-6TPQJ0/org.freedesktop.Platform.Locale-
37ALJ0/repo-WTmN4b-lock".
Access to the file has been denied
Searching the Google webs didn't really give me anything except this note on Github
https://github.com/flatpak/flatpak/issues/3512
Any suggestions to how to whitelist or otherwise ignore these files?
$ flatpak --version
Flatpak 1.4.3
NAME="Ubuntu"
VERSION="19.10 (Eoan Ermine)"
ID=ubuntu
VERSION_ID="19.10"
The savlog or syslog might give more information about what error SAV is hitting trying to scan the files.
/opt/sophos-av/bin/savlog -100
tail /var/log/syslog
It's likely that the files will need to be excluded, which you can using savconfig
/opt/sophos-av/bin/savconfig exclude /var/tmp/flatpak-cache-*

Troubleshooting PostgreSQL performance issue

I have a data ware house running on PostgreSQL and I would like to check what all are the missing indices are in my database.
I tried to install the extension pg_qualstats but it is giving the below error.
root#Ubuntu-1604-xenial-64-minimal ~ # sudo pip install pg_qualstats
Collecting pg_qualstats
Could not find a version that satisfies the requirement pg_qualstats (from versions: )
No matching distribution found for pg_qualstats
You are using pip version 18.1, however version 19.2.3 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
root#Ubuntu-1604-xenial-64-minimal ~ #
So how can i install this extension? I tried the CREATE EXTENSION pg_qualstats but it was giving error.
Also is there any other database maintenance need to be done for the database regularly?
What all parameter I have to check?
Can we automate the maintenance activity?
I was a SQL server DB admin and it was much easier to find out the missing index, understand the execution plan, DB maintenance but I find it hard, when it comes to PostgreSQL.
So any guidance will be of great help.
I am only answering the immediate question regarding the installation of pg_qualstats - the rest of the questions are way too broad for a platform like stackoverflow (or dba.stackexchange).
Many interesting extensions are provided as source code in Postgres (that's one of the reasons why it's highly recommended to run Postgres on Linux, because compiling the extensions is way easier in Linux than it is on Windows, and may extensions are only developed for Linux).
pg_qualstats is no different.
It is provided together with PoWA and the installation of the extension is documented as part of their installation guide
In a nutshell:
Download the source:
wget https://github.com/powa-team/pg_qualstats/archive/1.0.7.tar.gz -O pg_qualstats-1.0.7.tar.gz
tar zxvf pg_qualstats-1.0.7.tar.gz
cd pg_qualstats-1.0.7
the compile it:
make
make install
Register the shared libraries by editing postgresql.conf and after restarting Postgres the extension can be created using CREATE EXTENSION pg_qualstats;

Installing MATLAB Runtime on CentOS 7

I am trying to install the MATLAB Runtime (see www.mathworks.com/products/compiler/mcr) on Cent0S 7. I think I have installed MCR correctly because the install finishes through saying it completed after running
sudo ./install -mode silent -agreeToLicense yes
However, I am currently getting a error of:
Fatal error loading library /usr/local/MATLAB/MATLAB_Compiler_Runtime/v80/bin/glnxa64/libmwmclmcr.so Error: libXmu.so.6: cannot open shared object file
I have searched around on the forums and found a couple of post that indicate this may be an issue with either 32-bit vs. 64-bit libraries and/or X Windows. Also, I am pretty sure I am setting the following environment LD_LIBRARY_PATH and XAPPLRESDIR set variables correctly.
Has anyone out there successfully installed MATLAB Runtime on CentOS 7? Any help would be appreciated.
Thanks,
Derek
In case anyone else has this issue the following library install fixed the issue for me:
sudo yum install libXmu.x86_64

Problems installing/compiling DBD::mysql on OpenSuSE 10

I am getting a bunch of compile errors when I try to install the MySQL DBD::mysql Perl library. I am trying to install this library on OpenSuse linux (SUSE Linux Enterprise server 10 (x86_64) version 10, patch level 4)
The install fails when trying to compile dbdimp.h. There are hundreds of complile errors but I have reason to believe they all stem from the first 3:
dbdimp.h:23:49: error: mysql.h: No such file or directory
dbdimp.h:24:45: error: mysqld_error.h: No such file or directory
dbdimp.h:26:49: error: errmsg.h: No such file or directory
I believe that the reason I am getting the errors above is that I have no MySql Client installed. I do not know how to install mysql client (I believe I am supposed to get some version of libmysqlclient).
I am brand new to opensuse and vaguely familar with installing packages on Linux in general have used yum, yast, apt-get on ubuntu + centOS previously but the only package manager tools that seem to be on OpenSuse 10 are rpm and zypper. I have not managed to install the required mysql client using either of these. If anyone knows how to install MySql Client to resolve my issue I would greatly appreciate any recomendations
Thanks
You need to install MySQL or the MySQL client libraries, either through your system's package manager or by following the installation instructions from the source code.
It sounds like your question is really "How do I install MySQL on OpenSuse", which would be more appropriate for one of the other StackExchange sites.
I was able to resolve this to a point. In my original question, I stated that I had tried using YAST but that it had not worked. In fact, I did not fully explore the YAST install option but when I did, I managed to download install the required librarys by following an article I found (http://adminramble.com/install-mysql-yast/#chitika_close_button)
I was able to open the YAST GUI in the terminal window (not an X-window display) and navigate through the "software management" section wherein I was able to do a search for MySql. Amoung the search results were mysql client libraries, which I then selected and hit "Accept". The installation started and completed successully.
In order to complile the PERL DBD::mysql module, I had to create a new makefile with the ccflags specified so that the header files could be found:
perl Makefile.PL --cflags -I/usr/include/mysql
I say "to a point" at the top of this comment because I then ran into further problems compiling but my original issue posted has been partially resolved and getting this far may help someone else who is experiencing the same problem. Will update if I get a solution to the compile problem.