What To Do If You Lock Your Keys In Your Car?

That dreaded feeling when you go to find your keys and you realise they are sitting on your seat or you’ve locked them in the boot of your car.  Most of us have been there and it’s often at the most inconvenient times. Remember there is always a way into your car and someone is here to help you.

The first steps

• Don’t panic, remember being late isn’t the end of the world;
• Call anyone that needs to know that you are held up and then work the next steps to getting into your car;
• Double check to see if any doors including your boot are unlocked (if not already done so);
• Do you have a spare key at your home or with a family member? Arrange for the spare key to be collected and bought to you by a friend or family member.
• Call your local Automotive locksmith. Here at Evolution Lock Service we can often get to you and have you in your car within 20-30minutes, potentially even quicker!

 

Your child/pet is locked in the car!

This is an emergency situation especially in the Australian summer heat, what do you do?

• Call us immediately for a priority job and if you think your child is distressed or needs medical assistance call 000 for an ambulance.

Call your local locksmith for assistant

Why not just smash a window? Car windows are often costly and will have you making calls and spending your time without your car to arrange a replacement.  Our automotive locksmith is never too far away and will be able to get you into your car without damaging it at all.  Our trusted and skilled automotive locksmiths have the skills to lishi pick your car open or air wedge some cars where picking it open isn’t possible.  This means there are no scratches and the seals on your windows/doors won’t be damaged at all.

We can get into ANY car and have you back on the road quicker. So call us today on 0423 372 098

 

Don’t have a spare key?

We highly recommend you have a spare key either with a trusted friend/family member or locked away in your home. That way when and if this situation arises again you have a spare that can be collected to get you into your car without having to call us out.

Spare keys made are much cheaper than having all keys lost and starting from scratch, this is because the car already has a programmed key to work from and we are programming extra keys.

We can give you a quote onsite or over the phone for a spare key. You can call us on 0423 372 098 for an obligation free price.

How to avoid the situation happening to you again.

Here are a few options/ideas for avoiding being locked out of your car again:

• Keep a spare key in a section of your bag or at another location at all times.
• Don’t have a spare? Call us on 0423372098 to arrange for one of our automotive locksmiths to come to you to arrange a spare key to be made.
• Don’t allow small children to play with your keys when you aren’t in the car with them.
• Always take your keys out of your car when the door is shut as some cars have an auto lock function.
• Going to the beach is much more fun without losing a key, keep your key clipped to a bag so it can not fall off. Finding a key in the sand is a hard job!
• Regularly replace the battery in your key

Hope you found this article helpful and for any questions, quotes or assistance with getting into your car call us on 0423 372 098.

The post What To Do If You Lock Your Keys In Your Car? appeared first on Evolution Lock Service.

from Evolution Lock Service https://evolutionlockservice.com.au/what-to-do-if-you-lock-your-keys-in-your-car/

The Chubby Lock Service for Loosely-Coupled Distributed Systems, Burrows, OSDI 2006

I didn't read this paper before class, because I thought I had read it earlier. It turns out I hadn't and I was confusing it with the "Paxos Made Live" PODC 2007 paper. I realized this only towards the middle of the class :-) The "Paxos Made Live" paper focused on the Paxos consensus implementation that makes the state replication and availability work in Chubby. In contrast, this Chubby Lock Service paper focuses only on the lock service part and is very client-centric. It is the need and uses cases of the clients (i.e., the programmers in Google) that has dictated the design of the service and the interfaces, and even the presentation of the paper.

Chubby serves course grain locks rather than fine-grained locks to keep the load light. The paper mentions that the primary goal is to provide reliability/availability and thruput/storage are secondary goals.

Chubby uses Paxos for consistent state replication among the five machines in the Chubby cell. The details of this process is best left to the "Paxos Made Live" paper. Paxos is simple yet could be hard to internalize. When I am teaching the distributed systems class, I dedicate one week solid to the Paxos algorithm so that students have time to understand and internalize the algorithm. As far as this paper is concerned, the thing to keep in mind from the Paxos algorithm is that the master performs a write (for installing a lock) by contacting all the replicas and getting an acknowledgement from at least the majority of the replicas that write is performed. So, writing takes time, the master has to clear everything with the other replicas first before responding to the client that the write is performed. The read is quicker, the master can serve the reads locally. This is achieved by using a lease on the replicas; while the lease holds the replicas promise they will not choose a new master, so the master is guaranteed that it has the latest information and can serve reads locally. (This lease should not be confused with the lease to clients that will be mentioned below.)

OK, let's proceed to discuss the meat of the paper. I have to confess that there are several things I could not understand in this paper. Maybe this is because I have more of an academic background and little background as a programmer, the intended audience of the paper. The students in the seminar also were not any successful than me in answering the questions I raise below.

Chubby provides an interface much like a distributed file system with advisory locks. A typical name is: "/ls/foo/wombat/pouch" where ls stands for lock service, and foo is the name of a Chubby cell, the remaining path is the file that holds the metadata for the lock. "Locks are advisory" means that locks conflict only with other attempts to acquire the same lock: holding a lock called F neither is necessary to access the file F, nor prevents other clients from doing so. The author states the reason for this decision as "Chubby didn't want to break other clients", "We rejected mandatory locks, which make locked objects inaccessible to clients not holding their locks." But I don't understand how you can have an application that uses locks and one that ignores locks run at the same datacenter without giving up consistency and sanity perhaps. Is there an assumption about the filesystem that it will check with Chubby if a client without a lock is trying to acccess a file with a lock?

A lot of the paper is devoted to explaining the lease to clients and client-side caching of the locks to reduce the traffic to the master. Caching is all about improving performance via leases, so that the client doesn't need to read-request the lock from the master everytime it wants to check it. And it turns out the programmers were really in the habit of busy-waiting on the locks. This is from page 13 of the paper: "Originally, we did not appreciate the critical need to cache the absence of files, nor to reuse open file handles. Despite attempts at education, our developers regularly write loops that retry indefinitely when a file is not present, or poll a file by opening it and closing it repeatedly when one might expect they would open the file just once."

So, what the Chubby system does is to solve this problem for the clients. Chubby master makes the clients cache the locks, and promises to contact the client when that cache needs to be invalidated. So, the client does the busy-waiting on the lock in its cache without overwhelming the master with read-requests. This is how the paper puts it: "Chubby clients cache file data and node meta-data in a consistent write-through cache held in memory. The cache is maintained by a lease, and kept consistent by invalidations sent by the master, which keeps a list of what each client may be caching."

Keep alive messages are employed to extend the client leases with the master. I really like this idea. The client asks for a lease extension via an RPC, and the master, upon receiving this rpc, blocks the RPC and answers it (granting the lease) only close to the end of the lease. This allows the master to extend lease with max time and little overlap. I guess this process could have been at the master immediately on receving the request if the reply referenced a physical time rather than a period. But then replying early is a disadvantage for the master: What if it grants the lease too early (then it is promising for a long interval in the future), and it dies right after this reply. Then availability suffers, because first the gap and then the lease need to be waited. There is a reason the client is not sending the request toward the end of the lease and i rather sending it early on. This is because if the master is down, the client can find this out early on with this check to the master and plan accordingly. Another advantage of this RPC mechanism is that the notifications from the master to the client is piggybacked to the callback on the keep alive RPC. This way firewalls are not an issue for the master.

I found the Section 2.9 on failovers very complicated. This section talks about how the caches and leases can survive a master failover (new master selection in Chubby) with least interruption as possible. The paper also acknowledges this: "Readers will be unsurprised to learn that the fail-over code, which is exercised far less often than other parts of the system, has been a rich source of interesting bugs." There are all sorts of things to deal with in a failover. The new master tries to construct the leases the old master has distributed to the clients by observing the old handles the clients use to refer the files (handles include a sequence-number that allows a master to tell whether a handle was generated by it or by a previous master), and tries to keep these sessions alive seamlessly as much as possible.


First seen on: http://muratbuffalo.blogspot.com/2010/10/chubby-lock-service-for-loosely-coupled.html