Gordan is available for hire
Hire GordanGordan Bobic
Verified Expert in Engineering
Software Developer
Location
Sofia, Bulgaria
Toptal 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.
Portfolio
Shutterstock
SQL Triggers, SQL, Amazon Web Services (AWS), KVM, CentOS, ZFS, MariaDB...
Zolo Ventures Ltd
SQL, MySQL, Database Administration (DBA), MariaDB, Optimization, MySQL Server...
Pure360
SQL, VMware ESXi, Perl, Linux, ZFS, Amazon Web Services (AWS), MySQL...
Experience
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.
Work Experience
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, Amazon RDS, Database Administration (DBA), Database Replication, Big Data
MySQL DBA Database Engineer
2019 - 2019
Zolo Ventures Ltd
- Carried out extensive database optimization and significantly reduced page load times.
- Deployed additional servers for analytics and read requests.
- Deployed a performance monitoring and alerting system.
Technologies: SQL, MySQL, Database Administration (DBA), MariaDB, Optimization, MySQL Server, SQL Performance
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, Amazon RDS, Database Administration (DBA), Database Replication
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 Administration (DBA), Database Replication, MySQL Server
Database Specialist
2017 - 2017
Investis
- Delivered performance optimizations in the client's stored procedures on their MySQL RDS databases.
- Developed existing operations on the client's 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, Amazon RDS, Database Administration (DBA), Database Replication, SQL Performance
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, Amazon RDS, Database Administration (DBA), Database Replication
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, Amazon RDS, Database Administration (DBA), Database Replication
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, Database Administration (DBA), Database Replication
MySQL Database Engineer
2012 - 2013
Adfonic
- Optimized and improved the database infrastructure containing approximately 100 TB of data, based on Red Hat 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, Database Administration (DBA), Database Replication, MySQL Server, SQL Performance, Big Data
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, Database Administration (DBA), Database Replication
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, Database Administration (DBA), Database Replication
Senior Database Administrator (DBA)
2011 - 2011
Lumesse
- Resolved stability issues, improved the performance, and redesigned the server estate to ensure the 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 ESXi platform. This enabled the massive reduction in the MySQL server estate's size (and cost) while still providing better performance.
- Upgraded MySQL servers from 5.0 running on Debian Linux to 5.1 running on Red Hat Enterprise Linux 6 with negligible downtime.
Technologies: SQL, VMware ESXi, VMware, RHEL, MySQL, MySQL DBA, Performance Optimization, Performance Tuning, Query Optimization, Optimization, Database Administration (DBA), Database Replication, Data Recovery, MySQL Server, SQL Performance
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, Database Administration (DBA), Database Replication
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, Database Administration (DBA), Database Replication
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, Database Administration (DBA), Database Replication
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, Database Administration (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, Database Administration (DBA), Database Replication
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, Database Administration (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, Database Administration (DBA)
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, Database Administration (DBA), Database Replication
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, Database Administration (DBA)
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, Database Administration (DBA)
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, Database Administration (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, Database Administration (DBA)
Experience
RedSleeve Linux
https://github.com/redsleeve-linuxI 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
ROLE: Founder
ZFS FUSE
https://github.com/gordan-bobic/zfs-fuseA 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
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/shatteredsiliconPercona 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
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, Docker
Storage
MySQL, PostgreSQL, Linux File Systems, MariaDB, SQL Stored Procedures, SQL Triggers, Database Triggers, InnoDB, MyISAM, Databases, Database Administration (DBA), Database Replication, DRBD, MySQL Clustering, MySQL Server, SQL Performance
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, Amazon RDS, Data Recovery, Big Data
Education
1997 - 2000
Bachelor of Science (BSc) Degree in Computer Science
Royal Holloway, University of London - Egham, Surrey, England
Certifications
OCTOBER 2012 - PRESENT
Certified MySQL Developer
Oracle
OCTOBER 2012 - PRESENT
Certified MySQL Database Administrator
Oracle
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