===Parallelism Problems in STL===
Put Within STL, issues arise when you attempt to access containers in parallel. With containers, when threads update the container say with push back, it is difficult to determine where the insertion occurred within the container(each thread is updating this container in any order) additionally it the size of the container is unknown as each thread may update the size as it goes. For example, in a picture and maybe vector we can push some code data to it in parallel but knowing where that data was pushed to requires as to search the vector serially for that data's location. If we attempt to find the data in parallel, 1 thread could search for the data, but another could update the vector during that time which causes problems with thread 1's search. Locks can solve the above issue but cause significant performance issues as the threads are forced to wait for each other. Picture here
===Lock Convoying in TBB===
Put another picture here