[Cppcms-users] Fw:sorry to ask this question but i do not know where to ask

[郭春晓 <rj...@12...>]

-------- Forwarding messages --------
From: "郭春晓" <rj...@12...>
Date: 2012-07-27 11:57:16
To: art...@ya...
Subject: sorry to ask this question but i do not know where to ask

Hi all:
In high performance server,we all see the code as follow.
typedef union
{
  erts_smp_rwmtx_t rwmtx;
  byte  cache_line_align_[ERTS_ALC_CACHE_LINE_ALIGN_SIZE(sizeof(erts_smp_rwmtx_t))];
}erts_meta_main_tab_lock_t;

erts_meta_main_tab_lock_t    main_tab_lock[16];

what can cache_line_align_  do and the benefit of it ?