Tech Force - blog sobre tecnologia

Thousands concurrent parallel read write accesses over tens of millions of small files is a terrible performance tuning problem for e-mail servers. You must understand and fine tune all your infrastructure chain, following the previous articles for data storage and multipath on Debian 5.x Lenny. We reduced the CPU I/O wait from 30% to 0,3% (XFS) and 5% (EXT3) with these combined previously undocumented file system tuning tips. Mainframes have excellent parallel I/O performance. Data storage systems could deliver parallel I/O performance to Debian GNU/Linux if you configure them , your multipath connections , undestand the concepts, application behaviour and follow some hints for confguring and tuning your LVM, RAID, XFS, EXT3. The key word is  PARALLEL . Fiber channel data storage systems, multipath connections, excell at parallel I/O. These days of multicore, multi gigabyte RAM, fiber channel and many channels gigabit connec...

The IBM DS 8300 Data Storage Systems were multi millions dollars flexible high availability and performance SAN machines. But you may left much of such performance and availability behind if you do not configure them correctly for Debian GNU / Linux. See how to ask for performance data storage space on them. Or what you need to configure on them. Read about an actual configuration running with Debian GNU / Linux hosts at SERPRO. Essential concepts about IBM Data Storage performance The IBM DS architecture was born for mainframe use. So you need to understand some different concepts / naming from the Debian GNU / Linux regular ones. The IBM DS 8300 hardware and software (it is a multi cpu Power AIX machine) is  optimized for highly parallel I/O requests . The IBM DS 8300 hardware could be "logically partitioned" (LPAR) in order to guarantee quality service levels (space, latency, transfer speed) and LPARs could be grouped into Storage Facility Images (SFI) f...

Este é o primeiro de uma série de artigos sobre ZFS e Btrfs. Abordaremos desde situação legal do código fonte, apresentação básica do funcionamento para administradores de sistemas, passando por tuning, thin provisioning, tiered storage e configurações de alto desempenho, até dicas de como adquirir ou montar seu Data Storage de alto desempenho, com uma boa BIBLIOGRAFIA selecionada. Este artigo não é um tutorial iniciante. É um resumo de lições aprendidas. Leia a bibliografia selecionada para detalhes. Esta parte 1 é focada nos tópicos para análise e consideração no projeto. Apresentação básica do funcionamento ZFS para administradores de sistemas Do ponto de vista do administrador de sistemas, ZFS engloba as funções de sistema de arquivos POSIX transacional Copy On Write CoW com checksum e tamanho de blocos dinâmico, gerenciador de snapshots e clones, gerenciador de volumes, gerenciador de dispositivos de blocos e hot spares, RAID, servidor de arquivos NFS, servidor d...