+Joshua Smith
>From my reading, M/S seems to have better throughput than HR, at the
expense of more frequent downtime,
>and spurious datastore timeouts. I'd like to have that option in a
multi-threaded app.
This is more important for public app (site) with many anonymous users.
My app is 100% user based - e.g. used after log-in, but heavy on data
related to each particular user.
The users are not accessing it very often (say they access it many times a
day but this is not much)
but when they access it they need to be as fast as possible.
So *frequent downtime *is a non-issue, the chance a user to access it at
exactly this time are minimal,* *
*spurious datastore timeouts *is a non-issue because this is rare - so I can
live with Master / Slave
imperfections - it is good enough and I don;t need to rewrite and optimize
again.
+Ikai Lan
>Master/Slave doesn't have better throughput. In the 99th percentile,
because of datastore latency spikes,
>high replication far outperforms master/slave.
I think Master/Slave is a lot faster in my case up to 10 times faster. I
tested it with only read, no write operations,
no transactions, nothing special for example I have a heavy use of this
expression:
*
e = MyList.get_profile(email)
*
*
my_keys = e.my_keys
my_members = db.get(my_keys)
for member in my_members:
member.<property>, etc. <-- do something with the
property
*
*and it is parallel in Master/Slave (according to Brett Slatkin
presentation) . In High Replication I believe it is serial,*
*probably I am wrong (I don't have a way to know) but this operation is very
slow in High Replication.*
*
*
*My code uses heavily this construct and it is extremely fast.*
*
*
*Best,*
*
*
*--Constantine*
*
*
*
*
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