I have checked the code. Yes, the mmap opened readonly, "read_only (@c
opt = 0) mode".
But this lead to call mmap using MAP_PRIVATE flag (not shared).

To share mmap between process, one must mmap using MAP_SHARED.
So I think this mmap wouldn't be shared between process.

Is this expected behavior?

-Aris

On 2/9/15, K. John Wu <[email protected]> wrote:
> Hi, Aris,
>
> In all cases, FastBit is doing memory map on read-only content.
> Therefore, the system should be able to safely share the content among
> different processes. Hope this helps.
>
> John
>
>
> On 2/8/15 7:17 PM, Aris Setyawan wrote:
>> Hi John,
>>
>> Is fastbit memory mapped file, shared between process?
>>
>> I plan to use fastbit from php-apache, which have multiple process
>> architecture.
>> If the memory mapped file shared, I can save a lot of memory.
>>
>>
>> Regards,
>> -aris.
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