The phrase "message backlog" is a grammatically correct term, and it can be used in written English.
An example sentence might be: "We're working to clear the message backlog in our customer service system."
This includes shared bank account statements, a certificate of marriage, text message backlogs, up to date medical exams, gigabytes of photos, letters from friends and family, screenshots of Facebook relationship status, Facebook wedding announcement threads, shared bills, signed tenancy agreements, vacation itineraries, a strict timeline of your relationship, and numerous shared receipts.
On Thursday, more than 40 veterans representing 22 states met outside the Capitol to once again push their "break the backlog" message, this time to more than 100 congressional offices.
Meanwhile, the current Python-Oracle based consumers used by the WLCG, running on two production virtual machines, were struggling to keep up, causing a backlog of message stored in the broker.
But he added: "It's going to take some time with the backlog of messages that developed.
The total failure resulted in a backlog of messages that they are chewing through at this moment.
(Who knows if Snowden was lurking on the service under an assumed name prior to uncloaking as @Snowden. Someone has probably DMed him to ask but he clearly has a big backlog of messages to get through…).
The radio operator, Jack Phillips, may have failed to grasp its significance because he was preoccupied with transmitting messages for passengers via the relay station at Cape Race, Newfoundland; the radio set had broken down the day before, resulting in a backlog of messages that the two operators were trying to clear.
The boards are now back, and the Friends Reunited team are currently wading through a backlog of 500,000 messages.
When he left, he said he would meet Jenny soon to go through a backlog of Facebook messages and buy a laptop.
An outpouring of support from around the country has paralyzed the Village Hall telephone system, with a team of volunteers working to clear a backlog of voice messages.
