Bosen, baba. Cha kheye jao, ekhono garam achhe. I have run this boarding mess of four rooms in Sutrapur for nineteen years, on a lane off the side of Tipu Sultan Road that the rickshaw wallahs still call Mostofa Mia's lane even though Mostofa Mia died in 2009. My husband kept this register. After he passed I kept it, and my eldest boy who works in some bank in Banani keeps asking me to use a spreadsheet, which is exactly what a boy who has not slept under his own roof in nine years would say.
Saquif bhai came to interview me about "caching", which the boys with the laptop bags call what I do here.
They think it is a computer thing.
I asked him to define the word, and he stumbled for forty seconds before he said it is the question of who you let stay in the spare room and for how long. So then, yes, it is what I do, and the only new thing is the angrezi name.
Look at the page. Six columns ruled in faint blue across the spread. Guest, room, arrived, charge per night, last paid, notes. Every line of this khata is one decision I have already made about somebody, and most of those decisions were made in my hand the moment I wrote the line down. The notes column is where I cheat. Rashid bhai's note is "twelve years, has a key copy". Tutul's note is "BUET final year, owes me four nights". Comilla khala's note is "five days, niece's wedding, do not charge". Faruk's note is "lapsed, three weeks, evict by Friday", and Friday came yesterday, so I crossed his line out with red ink this morning before fajr.
The boys who came here from a startup in Mohakhali last year, two of them, kept saying I should use something called "LRU". I told them I have been using LRU since 2007, just without the angrezi name. The one who has not paid in the longest is the one who leaves. Rashid bhai is the exception because the rule was made for boys who think of this place as a stop on the way somewhere else, not for the man who repaired my fan three monsoons in a row without being asked. The boys with the laptop bags call this exception "pinning", which is a polite word for what I learned from my mother in law in 1994 as good manners.
The TTL takes the boys with the laptop bags two cups of cha to grasp. Time to live, they call it, meaning how long a guest is allowed to sit in the register before they expire. Comilla khala's TTL is five nights, because that is what she said at the door, and I wrote it on the chalkboard behind her head before she had taken her chappal off. The TTL works as a promise more than a maximum. After five nights I have the right to ask, but I rarely use the right on family, because the cost of using it is higher than the cost of one more warm bed. A stranger gets three nights, paid up front, no extensions on the first stay. The second visit, the TTL becomes a week and what was paid up front becomes a deposit.
Brian Bulkowski, who used to run caching at Netflix and is not Bangladeshi, gave a talk Saquif bhai made me watch on his phone. The line that stuck was that the size of the cache, in the end, matters less than the policy. He was talking about machines with 64 gigabytes of memory and movies people had not finished. I was thinking about my four rooms and Faruk in room three. You will never have enough beds for everyone who knocks, so the interesting question is the order in which you say no, and whether the boy who got the "no" today will speak well of you in the lane tomorrow.
who stays, who pays, who leaves before noon.
bua's rule today
khala gets the spare room. Five nights, no questions, the kettle is on.
The boys with the laptop bags keep treating this like a storage problem, when the whole of it has always been a hospitality problem. Martin Kleppmann, who I am told is a professor somewhere cold, wrote a book with a chapter on caches, and Saquif bhai showed me a paragraph from it on his phone over the third cup. The paragraph said cache invalidation is one of the two hard problems in computer science. I told him yes, because in this house invalidation is the social question of when you tell Comilla khala her five nights are up, when you cross out Faruk's line, and how long Rashid bhai's exception holds against the steady pressure of new boys arriving every March. The answer is never on a clock; it is in the texture of the lane, in who else is watching, in whether the boy who got the "no" today has a mother who will ask his sister about it on Saturday.
The register, then, is the conversation I have with myself at the end of every day, on this stool by the kerosene stove, under the fan whose four blades have thrown the same shadow across this page since 2003. The brass keys are on their hooks behind me, one for each room, and the fourth hook is empty until I decide who gets room four tonight. The algorithm in any book Saquif bhai brings me is the line a clever boy in Mountain View finally writes down on a slide, six months after the bua of every mess on Tipu Sultan Road has lived through the same Faruk and crossed his row out in red.