For keeping written text as long as possible it matters which are the risks for various things that can happen to the text, because no writing method is equally resistant to all of them.
There are at least 4 dangers for a written text: mechanical rubbing, fading due to light, water and organic solvents (e.g. alcohol).
There are many pigment-based inks that are specified to be lightfast and resistant to water and organic solvents, according to various archiving standards. Such inks are available for fountain pens or they are used in certain kinds of roller pens.
If you use such inks on paper that is somewhat porous, they will also be resistant to rubbing. There are certain kinds of "permanent pens", which have excellent resistance to rubbing even when you write on surfaces like plastic, glass or metal, not only on glossy paper, and which may also be lightfast and waterproof, but the text written with such permanent pens is easily washed with alcohol or other organic solvents (like also for text written with ball-point pens).
So the answer depends on your goal, but usually what you want is either a roller pen or ink for a fountain pen that are clearly specified as being pigment-based, lightfast and waterproof, together with paper on which you have checked that rubbing does not remove the written text. When using fountain pens, one must check that the archival pigment-based ink is known to be compatible with the model of fountain pen, otherwise clogging may occur. (For example, I use pigment-based ink cartridges from Sailor Japan, seiboku or souboku, with Sailor fountain pens, so compatibility is guaranteed.)
While graphite-based pencils produce writing that is lightfast and resistant to solvents, in my experience the inherent rubbing of the sheets of paper when you handle the notebook, or whatever you had used for writing, leads over the years to a fading of the text, so I do not like this method.
There are at least 4 dangers for a written text: mechanical rubbing, fading due to light, water and organic solvents (e.g. alcohol).
There are many pigment-based inks that are specified to be lightfast and resistant to water and organic solvents, according to various archiving standards. Such inks are available for fountain pens or they are used in certain kinds of roller pens.
If you use such inks on paper that is somewhat porous, they will also be resistant to rubbing. There are certain kinds of "permanent pens", which have excellent resistance to rubbing even when you write on surfaces like plastic, glass or metal, not only on glossy paper, and which may also be lightfast and waterproof, but the text written with such permanent pens is easily washed with alcohol or other organic solvents (like also for text written with ball-point pens).
So the answer depends on your goal, but usually what you want is either a roller pen or ink for a fountain pen that are clearly specified as being pigment-based, lightfast and waterproof, together with paper on which you have checked that rubbing does not remove the written text. When using fountain pens, one must check that the archival pigment-based ink is known to be compatible with the model of fountain pen, otherwise clogging may occur. (For example, I use pigment-based ink cartridges from Sailor Japan, seiboku or souboku, with Sailor fountain pens, so compatibility is guaranteed.)
While graphite-based pencils produce writing that is lightfast and resistant to solvents, in my experience the inherent rubbing of the sheets of paper when you handle the notebook, or whatever you had used for writing, leads over the years to a fading of the text, so I do not like this method.