## Graphene – What happens to the maximum flow if we decrease the capacity of each edge by one constant?

Given a diagram $$G = (V, A)$$with source $$s$$fall $$t$$, Edge capacity greater than 1 (but not all the same), I know that if we reduce the capacity of an edge, the $$s, t$$-Maximum flow decreases by at most 1. But I would like to know what happens to maximum flow by reducing (or increasing) the capacity of all edges by one. I would be pleased about comments / findings. Thanks a lot!

## Network Flow – Create Capacity Chart for a List of Flights?

I have a list of flights and for each flight I have information such as source, destination, flight capacity, time of arrival, departure time. There are only 8 different values ​​specified in the source and destination columns. There are several flights between any two nodes, i. H. Several flights from LAX to PHX and similarly several flights from PHX to other destinations. Now I need to determine the capacity of the entire network, since our source is LAX and our target is JFK. I am determined to create a capacity graph or to determine the capacity of the entire network. Every idea or hint is greatly appreciated.

## Security – How could PSBT handle the data capacity limit of QR code?

QR code has a very limited data capacity. (According to Wikipedia) A single QR code can only contain <3 KB of binary data.

It's not uncommon for a PSBT to reach this 3 KB limit, especially for those who spend non-SegWit UTXOs.

SegWit offers the possibility to sign input values. However, to sign non-SegWit entries in the offline / hardware wallet, complete data from previous transactions is still required to validate the input values. Otherwise, it could be a security issue: A malicious party / malware could secretly manipulate the submissions to trick the user into paying an unexpectedly high amount.

## Performance – CPU Underutilized at high capacity

I have a MacBook Pro with a i9 processor and with Macos Catalina. I do a lot of CPU work every day, but the CPU is never 100% exploited. I use `Intel Power Gadget` to check my CPU performance. , The utilization never reaches 100%. But if I let that happen `Cine-bench Bench-mark` it reaches 100%. Can I know why this does not happen when I use another regular app that needs to be 100% busy to actually run faster? I've also made sure that the software I'm running is optimized to accommodate as many cores as possible. I hope you can share any configuration file that needs to be changed so that all processes can exploit 100% of the CPU.

## stored procedures – Error: New transaction can not be created because the capacity has been exceeded

We receive error messages from our SQL server when we run a stored procedure to increase a counter. This SP is often executed for different entities, but when run on a GLS tracking number, we sometimes get:

"New transaction can not be created because capacity has been exceeded"

The SP is run with a separate username to exclude it from the transactions in which the user resides.

What causes this error message?

## Algorithm – I do not have any of the best programming languages ​​for games. Is that really helpful enough to have a good capacity for games?

Yes, since C ++ is a high-level language that teaches you the basics of object-oriented programming, it is a good idea to learn it. It's also the language used to build most major console and Windows games. … C ++ is not an easy language to learn.

## If I have 51% of the capacity of the entire network, can I break down absolutely all the blocks faster than the network?

I'm really wondering if I can break down absolutely all blocks in the network faster than miners with their 49% hashing power, which is not intended for the purpose of a double-donation attack.

## Algorithms – Algorithm for updating the maximum flow due to the capacity increase

Let G = (V, E) be a flownet with source, sink and integer capacities. Assume that the maximum flow is in G f (and the value of the maximum flow is | f |).
Suppose we increase the capacity of a single edge (u, v) in E by 1.

(a). Discuss, considering the minimum quantity (s) in the original network G, how the increase in capacity in (u, v) can affect the given maximum flow or not. f.

(b) Specify an algorithm to update the maximum flow due to the increase in capacity in (u, v). What is its complexity?

## Can you help me with my capacity planning?

Make sure you ask the right question.

• Computers are cheap
• Future needs are very difficult to predict
• Plan the scaling and not the purchase in advance

If you do not know what you need, it means that you do not need much. If you have a hot website, you probably have an operations team that knows how much RAM, disk, I / O, network, etc. your app needs. When you are in the dream phase, you should start with your desktop and work your way up.

Make sure you have an idea of ​​how you scale as things get bigger. Can you add more servers behind the load balancer? Can you break the Redis server?

Even having your own data center is a puke. A data center (even if it's only a computer) is a distraction from your original purpose. You can not just buy a computer, turn it on and go away. They need air conditioning, air filtering, reliable power, reliable internet, backups, spare parts, physical space to grow, power capacity to grow, power cables that have not stumbled, and a host of other headaches.

## Channel capacity for data transmission

If the size of the transmitted data is 24 kbit, what is the optimal channel rate to deliver this data?