Gordan Bobic, Software Developer in Sofia, Bulgaria
Gordan Bobic

Software Developer in Sofia, Bulgaria

Member since June 18, 2020
Gordon is an expert database developer and database administrator (DBA) who has over 20 years of experience with Linux (preference for CentOS/RHEL), databases (MySQL, MariaDB, PostgreSQL), and development in a variety of languages. Besides having multiple years of in-depth experience under his belt, he also has a bachelor's degree in computer science and is certified as a MySQL administrator and developer.
Gordan is now available for hire

Portfolio

  • Shutterstock
    SQL Triggers, SQL, Amazon Web Services (AWS), KVM, CentOS, ZFS, MariaDB...
  • Pure360
    SQL, VMware ESXi, Perl, Linux, ZFS, Amazon Web Services (AWS), MySQL...
  • UKCloud
    SQL, CentOS, PostgreSQL, Galera Cluster, MariaDB, MySQL, MySQL DBA...

Experience

Location

Sofia, Bulgaria

Availability

Part-time

Preferred Environment

Unix, Linux, MySQL, MariaDB, CentOS, Linux RHEL/CentOS, RHEL, Percona, ZFS, MySQL DBA

The most amazing...

...MySQL system I've architected was capable of processing 30 billion records per day.

Employment

  • MariaDB Database Administrator (DBA)

    2018 - 2020
    Shutterstock
    • Migrated and updated a part of a large database estate (dozens of replica sets, hundreds of servers, hundreds of TBs of data) from bare-metal servers in multiple data centers to AWS and self-hosted KVM.
    • Used ZFS snapshot sending, XtraBackup, and mysqldump for large-scale data migration, depending on what was available and most appropriate for each server.
    • Installed a continuous incremental backup regime with hourly restore granularity using ZFS snapshot sending via sanoid/syncoid.
    • Implemented Percona monitoring and management (PMM).
    Technologies: SQL Triggers, SQL, Amazon Web Services (AWS), KVM, CentOS, ZFS, MariaDB, MySQL DBA, MySQL, Performance Optimization, Performance Tuning, Query Optimization, Optimization, AWS RDS
  • Senior Database Architect

    2014 - 2019
    Pure360
    • Redesigned a large MySQL database estate running on RedHat/CentOS Linux.
    • Alleviated concurrency contention bottlenecks in InnoDB, rewrote queries to improve efficiency, and improved indexes.
    • Tuned storage alignment, MySQL, and OS-level configuration and used ZFS to further improve performance and operational features.
    • Delivered performance improvement of 12x (1,200%).
    • Extensively tested the performance impact of moving to different cloud providers including AWS (Xen) and ESXi-based ones.
    Technologies: SQL, VMware ESXi, Perl, Linux, ZFS, Amazon Web Services (AWS), MySQL, Performance Optimization, Query Optimization, Performance Tuning, MariaDB, Optimization, AWS RDS
  • MySQL Database Administrator (DBA)

    2016 - 2018
    UKCloud
    • Troubleshot and optimized the database estate consisting of Galera/MariaDB and MySQL server clusters on a large VMware ESXi server estate.
    • Improved the run times of a number of regularly recurring tasks from hours down to minutes.
    • Deployed new high-availability PostgreSQL and MariaDB clusters.
    • Used DevOps methods to improve consistency and reliability.
    • Migrated legacy MariaDB/Ubuntu systems to PostgreSQL/CentOS-based replacements.
    Technologies: SQL, CentOS, PostgreSQL, Galera Cluster, MariaDB, MySQL, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization
  • Database Specialist

    2017 - 2017
    Investis
    • Delivered performance optimizations in the client's stored procedures on their MySQL RDS databases.
    • Developed existing operations on their PostgreSQL RDS databases.
    • Built overall database performance improvements in the 10x to 50x range compared to original implementations.
    Technologies: SQL Triggers, SQL Stored Procedures, SQL, Amazon Web Services (AWS), PostgreSQL, MySQL, Performance Optimization, Performance Tuning, Query Optimization, Optimization, AWS RDS
  • MySQL Database Administrator (DBA)

    2016 - 2016
    Rise Projects
    • Resolved database throughput bottlenecks (AWS, RDS, MySQL).
    • Achieved a 100x (10,000%) increase in database throughput in the first three days with minimal application changes.
    • Reimplemented the gathering of application dashboard statistics to be asynchronous, which alleviated a number of deadlocking hotspots.
    Technologies: SQL Triggers, SQL Stored Procedures, SQL, Amazon Web Services (AWS), MySQL, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization, AWS RDS
  • Data Architect

    2015 - 2016
    DVSA
    • Steered, as the database architecture specialist, the database design and implementation delivered by three separate suppliers across four separate projects.
    • Established processes to ensure that the back-end database solutions are maintainable, robust, and capable of performing in line with challenging availability and performance requirements over the long-term lifecycle of the system.
    • Oversaw the migration of databases from the previous cloud service provider to AWS (RDS).
    • Designed an exhaustive audit superstructure using shadow tables and triggers to be attached to the existing database design with minimal changes to both the database and the application stack above it.
    Technologies: SQL Triggers, SQL Stored Procedures, SQL, Perl, Amazon Web Services (AWS), MySQL, MySQL DBA, Performance Tuning, AWS RDS
  • Systems Architect | Administrator

    2013 - 2014
    Moorfields Eye Hospital
    • Architected a high availability managed service platform for the OpenEyes project, based on RedHat Enterprise Linux 6/RedSleeve, Linux 6, and VServer.
    Technologies: SQL, RHEL, MySQL DBA
  • MySQL Database Engineer

    2012 - 2013
    Adfonic
    • Optimized and improved the database infrastructure containing approximately 100 TB of data, based on RedHat Enterprise Linux 6 and MySQL (variants including Percona, MySQL, MariaDB, and MySQL Cluster).
    • Worked with compressed archive databases residing on a GlusterFS storage pool. Automated tasks using Perl and Bash scripts.
    • Implemented a selective, versioned backup system for MySQL database structures.
    • Developed an in-database job scheduler using stored procedures and scheduled events to facilitate parallelization of stored procedures to better leverage multi-core hardware.
    • Designed and implemented a new database ingress solution to boost the data throughput capacity from the old bottleneck of 170,000 transactions/second to several times that figure.
    Technologies: SQL Triggers, SQL Stored Procedures, SQL, Percona, MariaDB, MySQL Clustering, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization
  • ISP Developer

    2012 - 2012
    BSkyB
    • Worked on improving and optimising performance of the firmware update system for broadband devices.
    Technologies: SQL, Perl
  • MySQL Developer and Database Administrator (DBA)

    2012 - 2012
    Cube 19
    • Developed stored procedures and optimized the MySQL database performance of the client's business intelligence data warehouse system.
    • Tuned MySQL server and Linux OS; optimized indexes, rewrote queries and implemented materialized views maintained by triggers.
    • Delivered performance improvements of around 24x (2,400%).
    Technologies: SQL Triggers, SQL Stored Procedures, SQL, Linux, MySQL, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization
  • Unix Platform Architect

    2008 - 2012
    Atos
    • Designed and implemented new systems for the BBC. Projects involved load balancing technologies (Inlab's Balance and BalanceNG and Linux kernel level load balancing using LNLB). The platforms used were Solaris and RedHat Linux.
    • Updated LNLB code to be compatible with later kernels.
    • Resolved a major BBC iPlayer outage and rectified the complex MySQL database problem that caused it.
    Technologies: SQL, Perl, Solaris, RHEL, MySQL, MySQL DBA
  • Senior Database Administrator (DBA)

    2011 - 2011
    Lumesse
    • Resolved stability issues, improved the performance, and redesigned the server estate to ensure long term supportability of a client's replicated MySQL databases.
    • Resolved a long-term recurring table corruption issue.
    • Improved the performance of the database stack by over 20x (2,000%) on the same hardware and same VMware ESX platform. This enabled the massive reduction in size (and cost) of the MySQL server estate while still providing better performance.
    • Upgraded MySQL servers from 5.0 running on Debian Linux to 5.1 running on RedHat Enterprise Linux 6 with negligible downtime.
    Technologies: SQL, VMware ESXi, VMware, RHEL, MySQL, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization
  • MySQL Database Architect

    2010 - 2010
    Transactis
    • Optimized MySQL databases to meet the performance requirements in time for the launch of the software product.
    • Tuned the entire application stack including VMware configuration, Solaris and RedHat Linux, NAS MySQL, table structures, queries, and stored procedures.
    • Achieved performance improvements of several orders of magnitude.
    Technologies: SQL, VMware ESXi, Solaris, RHEL, MySQL, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization
  • Senior Database Administrator (DBA)

    2010 - 2010
    Via Vox
    • Tuned MySQL databases running on Debian Linux systems.
    • Handled the migrations to new hardware.
    • Implemented a redundant fail-over database solution based on block device mirroring (DRBD) and RedHat clustering, with secondary backups using MySQL replication.
    Technologies: SQL, DRBD, RHEL, MySQL, MySQL DBA
  • Messaging Engineer

    2009 - 2009
    Deutsche Bank
    • Worked in a team of system administrators responsible for the day-to-day running and maintenance of various messaging platforms.
    • Looked after systems running Sendmail, Mailman, Brightmail, and PureMessage spam filtering, PostgreSQL and bespoke messaging solutions on Linux and Solaris (9, 10, zones) with LDAP authentication.
    Technologies: SQL, Solaris, Linux, PostgreSQL
  • Systems Engineer

    2008 - 2009
    BT Global Services
    • Worked as a part of the team performing day-to-day administration and maintenance of a large Linux and Solaris based service delivery platform running bespoke software.
    Technologies: Solaris, Linux
  • Systems Administrator

    2007 - 2008
    Griffin Information Systems
    • Built a new email storage system based on RHEL and SAN-based clustered GFS storage with MySQL for metadata storage.
    Technologies: SQL, RHEL, MySQL
  • Software Engineer

    2007 - 2007
    Solartron Metrology
    • Wrote calibration software for measurement probes in C++.
    • Produced a calibration certificate generation system using Perl, with data stored in MySQL.
    Technologies: SQL, C++, Perl, CentOS, MySQL, MySQL DBA
  • Systems Engineer

    2006 - 2007
    UK2
    • Resolved a number of performance issues impacting the email system using MySQL clustering for authentication and metadata storage.
    • Introduced the use of virtualization for product testing.
    • Assisted with a large-scale data centre migration.
    Technologies: SQL, Xen, Perl, RHEL, MySQL Clustering, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization
  • Software Developer

    2006 - 2006
    Mobile Streams
    • Maintained a MySQL database containing metadata for all of the available downloads.
    • Developed additional interfaces for providing downloads to customers in Perl.
    • Introduced PersistentPerl to improve performance of the HTTP front-end.
    Technologies: SQL, Perl, RHEL, MySQL, MySQL DBA
  • Software Developer

    2006 - 2006
    Lorien Customer Focus
    • Wrote software for supply chain management for a major car manufacturer.
    • Wrote the software in Perl while preserving the data in a PostgreSQL database.
    • Optimization of queries to meet performance goals.
    Technologies: SQL, Perl, RHEL, PostgreSQL, Query Optimization, Optimization
  • Systems Architect

    2004 - 2006
    Hanover Park Services
    • Maintained and audited software for the customer's insurance selling platform.
    • Redesigned the system architecture to streamline the server estate and improved availability by introducing hot failover capability between servers.
    Technologies: SQL, Xen, Perl, RHEL, PostgreSQL, MySQL, MySQL DBA
  • Software Developer

    2002 - 2004
    Billco Group
    • Developed and maintained software for client's internal use.
    • Architected the platform for a new group-wide data and document sharing project, backed by FreeBSD servers running a Coda distributed file system and MySQL backed metadata storage.
    Technologies: SQL, Perl, FreeBSD, RHEL, PostgreSQL, MySQL
  • Software Developer

    2002 - 2002
    InterClubNet
    • Worked on the development of a sports management system for the clients' foreign customers.
    Technologies: SQL, Perl, RHEL, PostgreSQL, MySQL
  • Software Developer

    2001 - 2001
    The Real Adventure
    • Improved the reliability of the legacy systems.
    • Resolved and mitigated complex issues surrounding the legacy code's inability to cleanly handle transaction interruptions.
    Technologies: SQL, Perl, RHEL, PostgreSQL, MySQL, MySQL DBA
  • Software Developer

    2000 - 2001
    Selected Financial Investments
    • Developed software for heavily customizable news data aggregation.
    • Built software for stock market data aggregation.
    Technologies: SQL, Perl, RHEL, PostgreSQL, MySQL, MySQL DBA

Experience

  • RedSleeve Linux
    https://github.com/redsleeve-linux

    I was the first to put together the RHEL 6 port for armv5tel hardware architecture. I also worked on putting together the CentOS 7 port for the armv5tel. This involved putting together and developing patches for many software packages included in the distribution which didn't build or work on armv5tel out of the box. Over 100 packages in EL6 had to be fixed to make them work. This reduced significantly in EL7 as more upstream developers started paying attention to the ARM port.

    ROLE: Founder

  • ZFS FUSE
    https://github.com/gordan-bobic/zfs-fuse

    A FUSE-based port of ZFS. It is mainly intended for use on platforms where a native port isn't available such as armv5tel.
    I backported support for pool versions 27 and 28 from OpenZFS (ZFSonLinux and Illumos) so zfs-fuse is now at parity with other implementations (OpenZFS and Solaris) in terms of maximum on-disk format that is interoperable with other implementations. This is particularly useful when it comes to attempting data recovery where other implementations cause a kernel crash when importing a pool. I also backported the mount.zfs helper and added support for using zfs-fuse as the root file system.

    ROLE: Current Maintainer

  • PMM 1.x Maintenance
    https://github.com/shatteredsilicon

    Percona has moved on to PMM 2.x, which, unfortunately, I don't find to be quite as good and stable in some ways as PMM 1.x. Unfortunately, a few bugs have come up in the meantime that I needed fixed, which Percona has shown little interest in. So I maintain a code tree with the appropriate fixes required to keep PMM 1.x current, useful, and operational since I use it in my day-to-day work. Additionally, I maintain PMM Client source and binary RPM packages so that they can be built and used on platforms that Percona does not directly provide binaries for (e.g. aarch64).

    ROLE: Maintainer

Skills

  • Languages

    Perl, SQL, Bourne Shell, Stored Procedure, C++, C
  • Tools

    *nux Shells, VMware, KVM/Qemu, RPM, Systemd
  • Paradigms

    Database Design
  • Platforms

    Linux, Linux RHEL/CentOS, Percona, Unix, CentOS, Amazon Web Services (AWS), Solaris, Xen, FreeBSD, KVM, ARM Linux, CentOS 6, Fedora
  • Storage

    MySQL, PostgreSQL, Linux File Systems, MariaDB, SQL Stored Procedures, SQL Triggers, Database Triggers, InnoDB, MyISAM, Databases, DRBD, MySQL Clustering
  • Other

    RHEL, ZFS, Shell Scripting, Triggers, Galera Cluster, MySQL DBA, VMware ESXi, XFS, Relational Database Services (RDS), RPM Packaging, Performance Optimization, Query Optimization, Performance Tuning, Optimization, Computer Science, AWS RDS

Education

  • Bachelor of Science (BSc) Degree in Computer Science
    1997 - 2000
    Royal Holloway, University of London - Egham, Surrey, England

Certifications

  • Certified MySQL Developer
    OCTOBER 2012 - PRESENT
    Oracle
  • Certified MySQL Database Administrator
    OCTOBER 2012 - PRESENT
    Oracle

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