Hello, We actually used pidstat and iwatch to log disk activity of a given webmail client upon our cyrus murder/aggregator. The access pattern was ...err... "unwise", when compared with thunderbird, for example. The webmail client open account, then opens all folders, then lists all messages, for all folders, then reads entire content from all of them, one by one, then javascript order the entire list, then split the list in pages to render at screen... It can at least be configured to not read entire content from all of them, only headers, but still one by one... All these transactions caused disk writes (a "heavy" fs operation) to cache, index and header cyrus account files, and webservers and imap frontends load. When you have MANY msg into an inbox, this could be tragic. When you have many such simultaneous users, becomes a performance disaster. I suspect that other webmail clients have similar "unwise" access patterns. So, one should *aggressively* fine tune filesystem for small files writes/updates. The webmail clients could be redesigned to use wise imap command patterns. Could cyrus project publish some hints at site? Good luck. Andre Felipe Machado http://www.techforce.com.br/news/linux_blog/lvm_raid_xfs_ext3_tuning_for_small_files_parallel_i_o_on_debian
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