drj11

A short experiment on copying big files

File size is 1412908312

According to https://www.kernel.org/doc/Documentation/sysctl/vm.txt

/bin/echo 3 | sudo tee /proc/sys/vm/drop_caches

is used to remove file data and metadata from (kernel) RAM. We'll use it so we can get timings for copying a file cold,

drj11

conda iceberg rapid

module load apps/python/conda conda create --name aws . activate aws

to install awscli I had to

conda install -c bioconda awscli

drj11

Why Doesn't my webserver work?

What ports are being listened on?

netstat --listen --inet # warning IPv4 only

netstat --numeric --listen --tcp

netstat -peanut

drj11

a-acute: guaraná

a-dots: jäger, hälleflinta, ländler, schwärmerei

a-grave: déjà vu (phrase, alas)

a-hat: pâté, râle

a-ring: Ångström, ås

drj11

from hypothesis import given
from hypothesis.strategies import floats

@given(floats())
def test_divide(p, q):
    if q == 0: return
    assert p / q == p * (1 / q)

if __name__ == '__main__':
    test_divide()

drj11

Amazon Lightsail: Amazon are going after the low-end server market with a consolidated product. Primarily targetted at users of other VPS hosting services like Dreamcloud. Not useful for us yet. We'll keep an eye out.

AWS Research Cloud Program: Useful. Am signing up. There's a bundle of goodies, but in particular free network traffic for downloads to JISC (so all UK universities), and invoiced billing instead of credit card.

Refinery Groups: Anyone can create a group, they are the owner and can then add members to that group.

drj11

a=[1]
b=['b']
c=['c']
b.append(a)
c.append(a)
print(b)
print(c)
b[1].append('xyz')
print(b)
print(c)

drj11

def p():
    v = [0]
    def x():
        print(v)
    x()
    v = [7]
    x()

p()

drj11

SRDS - SECTION A

2016-08-09 David Jones

1) Achievements

Delivey of Refinery platform on AWS. This is underway. A basic version works and it continues to be refined.

Contributed to planning of CGT.

drj11

2016-07-27

Observing a presentation that was mostly text on a white background, displayed on a projector.

• black on white - good
• green on white - terrible
• blue on white - legible, but difficult to distinguish from black
• light blue on white - ok
• cyan on white - mostly terrible
• red on white - ok