[Issue#45]Trx-sys optimization #48
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zwang28
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trx_sys_t::rw_trx_set is implemented as std::set, which does a few quite expensive operations under trx_sys_t::mutex protection: e.g. malloc/free when adding/removing elements. Traversing b-tree is not that cheap either. This has negative scalability impact, which is especially visible when running oltp_update_index.lua benchmark on a ramdisk. To reduce trx_sys_t::mutex contention std::set is replaced with LF_HASH. None of LF_HASH operations require trx_sys_t::mutex (nor any other global mutex) protection.
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trx_sys_t::rw_trx_set is implemented as std::set, which does a few quite
expensive operations under trx_sys_t::mutex protection: e.g. malloc/free
when adding/removing elements. Traversing b-tree is not that cheap either.
This has negative scalability impact, which is especially visible when running
oltp_update_index.lua benchmark on a ramdisk.
To reduce trx_sys_t::mutex contention std::set is replaced with LF_HASH. None
of LF_HASH operations require trx_sys_t::mutex (nor any other global mutex)
protection.