Google screening

Some time ago, for reasons best known to themselves, a Google recruiter decided to “reach out” on the basis of my GitHub profile to see if I were interested in a role as a Site-Reliability Engineer or possibly a Software Engeering. This entailed a short (~30min) telephone interview to answer some questions. I made a note of those I recalled, in case anyone’s interested.

The hawk-eyed and keen-minded among you may discern a certain amount of ambiguity in answers to some of the questions – e.g., is the opposite of malloc(), free() or a garbage collector? are we assuming an Ethernet MAC address? – which the recruiter did not seem to be happy to deal with. But so long as my answer included a reasonable approximation to (presumably) the string they had written down, all was well.

• What is the Big-O complexity of quicksort?
• What is the search complexity for a red-black tree, a binary tree, a linked list, a hashtable, and a B-tree?
• What’s the opposite of malloc()?
• What are the semantics of an ACL?
• Which of the following fields are not part of the passwd file?
  • shell, comment, initial umask, login name, ui, home directory, gid, preferred lagnuage
• What does the fstat syscall do?
• What’s the default signal for kill?
• What’s in an inode?
• How do you make a socket accept inbound connections?
• How many bytes in a MAC address?
• What are the packets involved in a TCP connection setup?
• How many hosts are in a /23 subnet?
• What’s the DNS resource record type for an IPv6 address?
• Estimate the value of 2²⁴.

In the end, I passed even though I could only remember the name, not the number, of the default signal for kill. It then got mildly amusing: the next stage is apparently to “jump on a call” (sigh) with a recruiter and an engineer to work through some coding problems. I explained that I generally refuse to engage in whiteboard coding during interviews (it’s not a useful measure of anything useful, and I don’t see why I should). They said oh but of course I could do it on a call so it wouldn’t actually be a whiteboard. I said, yes I could but no I wouldn’t and I thought they were rather missing my point. They said really, it was very unusual for someone to refuse. I said, to be honest it makes little sense anyway given they contacted me because of all the code I’d written under my GitHub account. They said oh well.

And then some time later – 6 months I think – a different recruiter “reached out” to ask why the process had stalled and did I want to jump on a call.

I said No. They haven’t called back since. Oh well…